View source for Standards for Web Applications on Mobile

= Status =
This is the live copy of a document that the [http://mobiwebapp.eu MobiWebApp project] publishes every three month, reflecting the current status of the Web technologies that are the most relevant on mobile devices (latest release: [http://www.w3.org/2011/11/mobile-web-app-state.html November 2011]). Contributions to this document are very welcome.

TODO:
* look at [[BrowserTechnologies]]
* Microdata?
* I18N/Multiscripts: but what?
* EXI

= Intro =

<p>Web technologies have become powerful enough that they are used to build full-featured applications; this has been true for many years in the desktop and laptop computer realm, but is increasingly so on mobile devices as well.</p>

<p>This document summarizes the various technologies developed in W3C that increase the power of Web applications, and how they apply more specifically to the mobile context.</p>

<ol>
<li>[[#Graphics]]</li>
<li>[[#Multimedia]]</li>
<li>[[#Device Adaptation]]</li>
<li>[[#Forms]]</li>
<li>[[#User interactions]]</li>
<li>[[#Data storage]]</li>
<li>[[#Personal Information Management]]</li>
<li>[[#Sensors and hardware integration]]</li>
<li>[[#Network]]</li>
<li>[[#Communication]]</li>
<li>[[#Packaging]]</li>
<li>[[#Performance &amp; Optimization]]</li>
</ol>

<p><strong>Please note:</strong> Although this document focuses on technologies that may aid in the development of client-side Web applications for mobile devices, the specifications that the document mentions have all use cases that go well beyond the mobile application use case. For example, in addition to aiding in the development of client-side Web applications for mobile devices, W3C Widgets have been used as server side-applications, standalone applications, daemons, and as a Browser extension format. </p>

<p>The data in this report should be <strong>used with caution</strong>. Feedback on every aspect of this document should be sent to the author (dom@w3.org) and will serve as input for the next iteration of the document.</p>

<p>The features that these technologies add to the Web platform are organized under the following categories: [[#Graphics]], [[#Multimedia]], ([#Device_Adaptation]], [[#Forms]], [[#User_interactions]], [[#Data_storage]], [[#Personal_Information_Management]], [[#Sensors_and_hardware_integration]], [[#Network]], [[#Communication]], [[#Packaging]], [[#Performance_.26_Optimization]].</p>

<p>In each category, a table summarizes for each feature:</p>
<ul>
<li>which W3C specification defines the feature,</li>
<li>which W3C group is responsible of the said specification,</li>
<li>the stage of the specification in the W3C Recommendation track (see below),</li>
<li>the estimated stability of the document, i.e. how widely the document is expected to change, as estimated by the author of this report, with three levels: low (the document is mostly stable), medium (some parts are stable, others are expected to change significantly), high (the document is expected to evolve significantly),</li>
<li>some rough qualitative indication on availability of implementations on mobile devices, based on the author’s understanding of the mobile devices market</li>
<li>a link to the latest editors draft of the document,</li>
<li>a link to the test suite for the said feature.</li>
</ul>


<p>As a reminder, W3C creates Web standards by progressing documents through its [http://www.w3.org/2005/10/Process-20051014/tr.html#Reports Recommendation track], with the following stages:</p>
<ul>
<li>“Editors drafts” represent the current view of the editors of the specification but have no standing in terms of standardization.</li>
<li>“Working Drafts” are early milestones of the Working Group progress.</li>
<li>“Last Call Working Drafts” signal that the Working Group has determined that the specification fulfills its requirements and all the known issues have been resolved, and thus requests feedback from the larger community.</li>
<li>“Candidate Recommendations” trigger a call for implementations where implementers are invited to implement the specification and send feedback; Working Groups are expected to show the specification gets implemented by running test suites they have developed.</li>
<li>“Proposed Recommendations” manifests that the group has gathered sufficient implementation experience, and triggers the final review by W3C Members</li>
<li>“W3C Recommendations” are stable and completed Web standards; these documents only get updated rarely, through the “Edited Recommendation” process, as a results from errata collected by Working Groups.</li>
</ul>
<p>Prior to starting standardization, a Working Group needs to be chartered, based on input from W3C Members, often through the organization of a [http://www.w3.org/2003/08/Workshops/ workshop], or after the reception of a [http://www.w3.org/Submission/ W3C Member Submission].</p>

<p>W3C has recently set up [http://www.w3.org/community/ Community Groups], a new mechanism that allows anyone to do experimental work within the W3C infrastructure, under IPR rules that are compatible to transition the work to the W3C standardization process.</p>
== Graphics ==
<p><strong>[http://www.w3.org/standards/techs/svg SVG]</strong>, Scalable Vector Graphics, provides an XML-based markup language to describe two-dimensions vector graphics. Since these graphics are described as a set of geometric shapes, they can be zoomed at the user request, which makes them well-suited to create graphics on mobile devices where screen space is limited. They can also be easily animated, enabling the creation of very advanced and slick user interfaces.</p>
<p>The integration of SVG in HTML5 opens up new possibilities, for instance applying advanced graphic filters (through SVG filters) to multimedia content, including videos. SVG 2.0 is set to facilitate that integration and complete the set of features in SVG.</p>

<p>In complement to the declarative approach provided by SVG, the <strong><code>&lt;canvas&gt;</code></strong> element added in HTML5 enables a [http://dev.w3.org/html5/2dcontext/ 2D programmatic API] that is well-suited for processing graphics in a less memory intensive way. That API not only allows  to render graphics, but can also be used to do image processing and analysis.</p>

<p>Both SVG and HTML can be styled using <strong>[http://www.w3.org/standards/techs/css CSS]</strong> (Cascading Style Sheets); in particular, CSS3 (the third level of the specification) is built as a collection of specifications set to offer a large number of new features that make it simple to create graphical effects, such as rounded corners, complex background images, shadow effects (<cite>[http://www.w3.org/TR/css3-background/ CSS Backgrounds and Borders]</cite>), rotated content (<cite>[http://www.w3.org/TR/css3-2d-transforms CSS 2D Transforms]</cite>), animations (<cite>[http://www.w3.org/TR/css3-animations CSS Animations]</cite>, <cite>[http://www.w3.org/TR/css3-transitions CSS Transitions]</cite>), and even 3D effects (<cite>[http://www.w3.org/TR/css3-3d-transforms CSS 3D Transforms]</cite>).</p>

<p>Animations can be resource intensive — the possibility offered by the <cite>[http://www.w3.org/TR/animation-timing/ Timing control for script-based animations API]</cite> to manage the rate of updates to animations can help keep them under control.</p>

<p>Fonts play also an important role in building appealing graphical interfaces, but mobile devices are in general distributed with only a limited set of fonts. <strong>[http://www.w3.org/TR/WOFF/ WOFF]</strong> (<cite>Web Open Font Format</cite>) addresses that limitation by making it easy to use fonts that are automatically downloaded through style sheets, while keeping the size of the downloaded fonts limited to what is actually needed to render the interface.</p>

<p>NB: work on defining a [http://www.khronos.org/webgl/ 3D graphic API called WebGL] has started outside of W3C, as part of the [http://www.khronos.org/ Khronos Group]; this API has been built to be compatible with [http://www.khronos.org/opengles/ OpenGL ES], i.e. for embedded systems, and is intended to work on mobile devices.</p>


<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th rowspan="2">2D Vector Graphics</th><td><cite>[http://www.w3.org/TR/SVGTiny12/ SVG Tiny 1.2]</cite></td><td rowspan="2">[http://www.w3.org/Graphics/SVG/ SVG Working Group]</td><td class="high">Standard</td><td class="high">Finished</td><td>New version of SVG (SVG 2.0) in preparation</td><td class="high">Widely deployed (iOS, BlackBerry, WebKit on Nokia, webOS, Opera, Firefox, announced for Android, announced for Windows Phone)</td><td class="high">[http://www.w3.org/Graphics/SVG/Test/ High coverage]</td></tr>
<tr><td>SVG 2.0</td><td class="low">N/A</td><td class="low">N/A</td><td>[http://dev.w3.org/SVG/profiles/2.0/publish/index.html editors draft]</td><td class="low">N/A</td><td class="low">N/A</td></tr>
<tr><th>2D Programmatic API</th><td><cite>[http://www.w3.org/TR/2dcontext/ HTML Canvas 2D Context]</cite></td><td>[http://www.w3.org/html/wg/ HTML Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Mostly stable</td><td>[http://dev.w3.org/html5/2dcontext/ Updated regularly]</td><td class="high">Widely deployed (iOS, BlackBerry, Android, webOS, Opera, Firefox, announced for Windows Phone)</td><td class="medium">[http://w3c-test.org/html/tests/approved/canvas/ Good coverage]</td></tr>
<tr><th>Rounded Corners</th><td rowspan="3"><cite>[http://www.w3.org/TR/css3-background/ CSS Backgrounds and Borders]</cite></td><td rowspan="7">[http://www.w3.org/Style/CSS/members CSS Working Group]</td><td class="high" rowspan="3">Candidate Recommendation</td><td class="high" rowspan="3">Mostly finished</td><td rowspan="3">[http://dev.w3.org/csswg/css3-background/ Updated regularly]</td><td class="medium">Deployed as an extension in many mobile browsers</td><td class="low" rowspan="3">None</td></tr>
<tr><th>Complex background images</th><td class="low">Limited (?)</td></tr>
<tr><th>Box shadow effects</th><td class="low">Limited (?)</td></tr>
<tr><th>CSS 2D Transforms</th><td><cite>[http://www.w3.org/TR/css3-2d-transforms/ CSS 2D Transforms Module Level 3]</cite></td><td class="low">Working Draft</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/csswg/css3-2d-transforms/ Last update Sep 2011]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>3D Effects</th><td><cite>[http://www.w3.org/TR/css3-3d-transforms CSS 3D Transforms Module Level 3]</cite></td><td class="low">Working Draft</td><td class="low">First draft</td><td>[http://dev.w3.org/csswg/css3-3d-transforms/ Last update Mar 2011]</td><td class="low">Very limited</td><td class="low">None</td></tr>
<tr><th rowspan="3">Animations</th><td><cite>[http://www.w3.org/TR/css3-animations CSS Animations Module Level 3]</cite></td><td class="low">Working Draft</td><td class="low">First draft</td><td>[http://dev.w3.org/csswg/css3-animations/ Updated regularly]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><td><cite>[http://www.w3.org/TR/css3-transitions CSS Transitions Module Level 3]</cite></td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/csswg/css3-transitions/ Last update Jul 2011]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><td><cite>[http://www.w3.org/TR/animation-timing/ Timing control for script-based animations API]</cite></td><td>[http://www.w3.org/2010/webperf/ Web Performance Working Group]</td><td class="low">Working Draft</td><td class="low">Early</td><td>[http://w3c-test.org/webperf/specs/RequestAnimationFrame/ Regularly updated]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Downloadable fonts</th><td><cite>[http://www.w3.org/TR/WOFF/ WOFF File Format 1.0]</cite></td><td>[http://www.w3.org/Fonts/WG/ WebFonts Working Group]</td><td class="high">Candidate Recommendation</td><td class="medium">Mostly stable</td><td>[http://dev.w3.org/webfonts/WOFF/spec/ Last update Aug 2011]</td><td class="High">Good deployment</td><td class="medium">[http://dev.w3.org/webfonts/WOFF/tests/Format/Tests/testcaseindex.xht Good coverage]</td></tr>

</table>

== Multimedia ==

<p>HTML5 adds two tags that dramatically improve the integration of multimedia content on the Web: the <code><strong>[http://dev.w3.org/html5/spec/video.html#video &lt;video>]</strong></code> and <code><strong>[http://dev.w3.org/html5/spec/video.html#audio &lt;audio>]</strong></code> tags. Respectively, these tags allows to embed video and audio content, and make it possible for Web developers to interact much more freely with that content than they would through plug-ins. They make multimedia content first-class citizens of the Web, the same way images have been for the past 15 years.</p>

<p>While these tags allow to play multimedia content, the <cite>[http://dev.w3.org/2009/dap/camera/ HTML Media Capture]</cite> defines a <strong>markup-based mechanism to access captured multimedia content</strong> using attached camera and microphones, a very common feature on mobile devices. The recently chartered [http://www.w3.org/2011/04/webrtc/ Web Real-Time Communications Working Group] is building an [http://dev.w3.org/2011/webrtc/editor/webrtc.html API (<code>getUserMedia</code>)] to directly manipulate <strong>streams from camera and microphones</strong>, on which it will collaborate with the Device APIs Working Group to provide capture and recording capabilities (in replacement of its former [http://dev.w3.org/2009/dap/camera/Overview-API.html Media Capture API].)</p>

<p>Beyond recording, two additional APIs add multimedia manipulation capabilities to the Web platform. We have already mentioned the <cite>[http://dev.w3.org/html5/2dcontext/ Canvas 2D Context]</cite> API: it enables modifying images, which in turn opens up the possibility of <strong>video editing</strong>. In a similar vein, [http://www.w3.org/2005/Incubator/audio/ a W3C Incubator Group] has been working on an <strong>Audio API</strong> ([https://wiki.mozilla.org/Audio_Data_API Mozilla’s proposal draft]) that makes it possible to modify audio content, as well as analyze and synthesize sounds — this work serves as a basis to the newly chartered [http://www.w3.org/2011/audio/ Audio Working Group].</p>
      <p>Finally, the [http://www.w3.org/2011/07/DeviceAPICharter.html new charter of the Device APIs Working Group] includes an API for reading the current audio volume of a device, allowing to adapt the type of interactions with the user depending on that setting.</p>

<p>The combination of all these features mark the starting point of the Web as a comprehensive platform for multimedia, both for consuming and producing. The rising interest around bridging the Web and TV worlds (manifested through the [http://www.w3.org/2011/webtv/ W3C Web and TV Interest Group]) should strengthen that trend in the coming months. Mobile devices are expected to take a growing role in many users TV experience, providing a “second screen” experience, where users can find more information on or interact with a TV program they're watching via their mobile devices.</p>

<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Video playback</th><td>[http://www.w3.org/TR/html5/video.html#video <cite>HTML5</cite> <code>video</code> element]</td><td rowspan="2">[http://www.w3.org/html/wg/ HTML Working Group]</td><td rowspan="2" class="medium">Last Call Working Draft</td><td rowspan="2" class="medium">Stabilizing</td><td rowspan="2">[http://dev.w3.org/html5/spec/video.html#video Updated regularly]</td><td rowspan="2" class="medium">Good deployment</td><td class="low">[http://w3c-test.org/html/tests/approved/video/ Just started]</td></tr>
<tr><th>Audio playback</th><td>[http://dev.w3.org/html5/spec/video.html#audio <cite>HTML5</cite> <code>audio</code> element]</td><td class="low">[http://w3c-test.org/html/tests/approved/audio/ Barely started]</td></tr>
<tr><th rowspan="3">Capturing audio/video</th><td><cite>[http://www.w3.org/TR/html-media-capture/ HTML Media Capture]</cite></td><td rowspan="2">[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/2009/dap/camera/ Last update Apr 2011]</td><td class="low">Very limited</td><td class="low">None</td></tr>
<tr><td><cite>[http://www.w3.org/TR/media-capture-api/ The Media Capture API]</cite></td><td class="low">Working Draft</td><td class="low">Will be replaced by <code>getUserMedia</code></td><td>[http://dev.w3.org/2009/dap/camera/Overview-API.html Last update Dec 2010]</td><td class="low">None (?)</td><td class="low">None</td></tr>
<tr><td><code>getUserMedia()</code> [http://www.w3.org/TR/webrtc/ WebRTC 1.0: Real-time Communication Between Browsers]</td><td>[http://www.w3.org/2011/04/webrtc/ Web Real-Time Communications Working Group]</td><td class="low">Working Draft</td><td class="low">Early work</td><td>[http://dev.w3.org/2011/webrtc/editor/webrtc.html last updated Oct 2011]</td><td class="low">A few experimental ones</td><td class="low">None</td></tr>

<tr><th>Image &amp; Video analysis, modification</th><td><cite>[http://www.w3.org/TR/2dcontext/ HTML Canvas 2D Context]</cite></td><td>[http://www.w3.org/html/wg/ HTML Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Mostly stable</td><td>[http://dev.w3.org/html5/2dcontext/ Updated regularly]</td><td class="high">Widely deployed (iOS, BlackBerry, Android, webOS, Opera, Firefox, announced for Windows Phone)</td><td class="medium">[http://w3c-test.org/html/tests/approved/canvas/ Good coverage]</td></tr>
<tr><th>Audio analysis, modification</th><td>None</td><td>[http://www.w3.org/2011/audio/ Audio Working Group]</td><td class="low">N/A</td><td class="low">Not started</td><td>[https://wiki.mozilla.org/Audio_Data_API Mozilla Data Audio API], [https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html Google Web Audio API]</td><td class="low">None</td><td class="low">None</td></tr>
          <tr>
<th>Audio volume reading</th>
<td>N/A</td>
<td>[http://www.w3.org/2009/dap/ Device APIs]</td>
<td class="low">N/A</td>
<td class="low">Not started</td>
<td>N/A</td>
<td class="low">None</td>
<td class="low">None</td>
</tr>

</table>

== Device Adaptation ==

    <p>Mobile devices not only differ widely from traditional computers, but they also have a lot of variations among themselves, in term of screen size, resolution, type of keyboard, media recording capabilities, etc.</p>
    <p>The [http://www.w3.org/TR/DDR-Simple-API/ Device Description Repository API] is a unified server-side API that allows Web developers to retrieve data on the devices that are accessing their pages on a variety of device information database.</p>
    <p>A client-side equivalent has been proposed as part of the [http://www.w3.org/TR/system-info-api/ Systems Information API]; while that specification is being vastly revisited, the Device APIs Working Group expects to do further work on a device information API.</p>
    <p>To take advantage of the large variety of media capturing devices provided on mobile phones, the [http://www.w3.org/TR/media-capture-api The Media Capture API] offers some detailed indication on the features and capabilities these devices.</p>
    <p>[http://www.w3.org/TR/css3-mediaqueries/ CSS Media Queries] offer a mechanism that allows to adapt the layout and behavior of a Web page based on some of the characteristics of the device, including the screen resolution. [http://dev.w3.org/csswg/css-device-adapt/ CSS Device Adaptation] defines a set of CSS directives to define the size on which this layout should be based, relatively to the size of the underlying device — specifying what has been implemented using the <code>&lt;meta name="viewport"&gt;</code> element so far.</p>

<table class="simple" border="1">
<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th rowspan="3">Device information</th><td>[http://www.w3.org/TR/DDR-Simple-API/ Device Description Repository Simple API]</td><td>Device Description Working Group (now closed)</td><td class="high">Recommendation</td><td class="high">finished</td><td>N/A</td><td class="low">Limited</td><td class="high">[http://www.w3.org/2005/MWI/DDWG/drafts/api/test-report.html Good Coverage]</td></tr>
<tr><td>[http://www.w3.org/TR/system-info-api/ Systems Information API]</td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td class="low">Likely to be vastly reworked</td><td>[http://dev.w3.org/2009/dap/system-info/ Last update March 2011]</td><td class="low">N/A</td><td class="low">N/A</td></tr>
<tr><td>[http://www.w3.org/TR/media-capture-api/ Media Capture API]</td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td class="low">Likely to be vastly reworked</td><td>[http://dev.w3.org/2009/dap/camera/Overview-API Last update December 2010]</td><td class="low">N/A</td><td class="low">N/A</td></tr>
<tr><th rowspan="2">CSS-based adaptation</th><td>[http://www.w3.org/TR/css3-mediaqueries/ Media Queries]</td><td rowspan="2">[http://www.w3.org/Style/CSS CSS Working Group]</td><td class="high">Candidate Recommendation</td><td class="high">Mostly finished</td><td>[http://dev.w3.org/csswg/css3-mediaqueries/ Last update August 2010]</td><td class="high">Widely deployed</td><td class="high">[http://www.w3.org/Style/CSS/Test/MediaQueries/20100726/ Good coverage]</td></tr>
<tr><td>[http://www.w3.org/TR/css-device-adapt/ CSS Device Adaptation]</td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/csswg/css-device-adapt/ Last update Oct 2011]</td><td class="low">Experimental implementations</td><td class="low">N/A</td></tr>
</table>

== Forms ==
<p>The ability to build rich forms with HTML is the basis for user input in most Web-based applications. Due to their limited keyboards, text input on mobile devices remains a difficult task for most users; <cite>[http://dev.w3.org/html5/spec/ HTML5]</cite> address parts of this problem by offering new type of form controls that optimize the way users will enter data:</p>
<ul>
<li><strong>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#date-and-time-state date and time entries]</strong> can take advantage of a number of dedicated form controls (e.g. <code>&lt;input type="date"&gt;</code>) where the user can use a native calendar control;</li>
<li>the <code>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#e-mail-state &lt;input type="<strong>email</strong>"&gt;]</code>, <code>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#telephone-state &lt;input type="<strong>tel</strong>"&gt;]</code> and <code>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#url-state &lt;input type="<strong>url</strong>"&gt;]</code> can be used to optimize the ways user enter these often-difficult to type data, e.g. through dedicated virtual keyboards, or by accessing on-device records for these data (from the address book, bookmarks, etc.);</li>
<li>the <code>[http://dev.w3.org/html5/spec/common-input-element-attributes.html#the-pattern-attribute <strong>pattern</strong>]</code> attribute allows both to guide user input as well as to avoid server-side validation (which requires a network round-trip) or JavaScript-based validation (which takes up more resources);</li>
<li>the <code><strong>[http://dev.w3.org/html5/spec/common-input-element-attributes.html#the-placeholder-attribute placeholder]</strong></code> attribute allows to guide user input by inserting hints as to what type of content is expected in a text-entry control;</li>
<li>the new <code>[http://dev.w3.org/html5/spec/the-button-element.html#the-datalist-element &lt;datalist&gt;]</code> element allows to create free-text input controls coming with <strong>pre-defined values</strong> the user can select from.</li>
</ul>

<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Date and time entries</th><td>[http://www.w3.org/TR/html5/states-of-the-type-attribute.html#date-and-time-state <cite>HTML5</cite> Date and Time state of <code>input</code> element]</td><td rowspan="5">[http://www.w3.org/html/wg/ HTML Working Group]</td><td class="medium" rowspan="5">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#date-and-time-state Updated regularly]</td><td class="low">Limited</td><td class="low">None</td></tr>
<tr><th>Customized text entries (<code>tel</code>, <code>email</code>, <code>url</code>)</th><td>[http://www.w3.org/TR/html5/states-of-the-type-attribute.html#telephone-state <cite>HTML5</cite> telephone, email and URL state of <code>input</code> element]</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/spec/states-of-the-type-attribute.html#telephone-state Updated regularly]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>Input pattern</th><td>[http://www.w3.org/TR/html5/common-input-element-attributes.html#the-pattern-attribute <cite>HTML5</cite> <code>pattern</code> attribute]</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/spec/common-input-element-attributes.html#the-pattern-attribute Updated regularly]</td><td class="low">Very limited (?)</td><td class="low">None</td></tr>
<tr><th>Input hint</th><td>[http://www.w3.org/TR/html5/common-input-element-attributes.html#the-placeholder-attribute <cite>HTML5</cite> <code>placeholder</code> attribute]</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/spec/common-input-element-attributes.html#the-placeholder-attribute Updated regularly]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>Pre-defined values for text entries</th><td>[http://www.w3.org/TR/html5/the-button-element.html#the-datalist-element <cite>HTML5</cite> <code>datalist</code> element]</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/spec/the-button-element.html#the-datalist-element Updated regularly]</td><td class="low">Very limited (?)</td><td class="low">None</td></tr>

</table>

== User interactions ==

<p>An increasing share of mobile devices relies on touch-based interactions. While the traditional interactions recognized in the Web platform (keyboard, mouse input) can still be applied in this context, a more specific handling of touch-based input is a critical aspect of creating well-adapted user experiences. As a result, work has started on defining <strong>[https://dvcs.w3.org/hg/webevents/raw-file/tip/touchevents.html Touch Events in the DOM]</strong> (Document Object Model).</p>

<p>Conversely, many mobile devices use haptic feedback (such as vibration) to create new form of interactions (e.g. in games); work on a <strong>[http://dev.w3.org/2009/dap/vibration/ vibration API]</strong> has started in the [http://www.w3.org/2009/dap/ Device APIs Working Group].</p>

<p>But as the Web reaches new devices, and as devices gain new user interactions mechanisms, it also becomes important to allow Web developers to react to a more abstract set of user interactions: instead of having to work in terms of “click”, “key press”, or “touch event”, being able to react to an “undo” command, or a “next page” command independently of how the user instructed it to the device will prove beneficial to the development of device-independent Web applications. Work on <strong>abstract DOM events</strong> that would address this need is planned as part of the [http://www.w3.org/2010/webevents/ Web Events Working Group].</p>

<p>Mobile devices follow their users everywhere, and many mobile users rely on them to remind them or notify them of events, such as messages: the <cite><strong>[http://dev.w3.org/2006/webapi/WebNotifications/publish/Notifications.html Web Notifications]</strong></cite> specification proposes to add that feature to the Web environment.</p>

<p>Similarly, the addition in the [http://www.w3.org/2011/07/DeviceAPICharter.html new charter of the Device APIs Working Group] of an API to generate system beeps (rather than app-provided sounds) would facilitate the integration of the underlying system mechanisms to notify the user.</p>

<p>Mobile devices, and mobile phones in particular, are also in many cases well-suited to be used through voice-interactions; the [http://www.w3.org/2005/Incubator/htmlspeech/ <strong>HTML Speech</strong> Incubator Group] is exploring the opportunity of starting standardization work around a framework that would make it possible for users to interact with a Web page through spoken commands (see their [http://www.w3.org/2005/Incubator/htmlspeech/live/draft-20110203-requirements.html use cases and requirements].)</p>

<p>The hardware constraints of mobile devices, and their different usage context can make [http://www.w3.org/WAI/mobile/experiences mobile users experience similar barriers to people with disabilities]. These similarities in barriers mean that similar solutions can be used to cater for them, [http://www.w3.org/WAI/mobile/ making a Web site accessible both for people with disabilities and mobile devices] a natural goal. The [http://www.w3.org/TR/mwbp-wcag/ <cite>Relationship between Mobile Web Best Practices and WCAG</cite>] document look into these similarities.</p>
<p>[http://www.w3.org/TR/wai-aria/ <cite>WAI-ARIA</cite>] provides semantic information on widgets, structures and behaviors hooks to make Web applications more accessible, including on mobile devies.</p>


<table class="simple" border="1">
<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Touch-based interactions</th><td>[http://www.w3.org/TR/touch-events/ Touch Events Specification]</td><td>[http://www.w3.org/2010/webevents/ Web Events Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[https://dvcs.w3.org/hg/webevents/raw-file/tip/touchevents.html Updated regularly]</td><td class="high">Largely deployed</td><td class="low">None</td></tr>
<tr><th>Vibration</th><td>[http://www.w3.org/TR/vibration/ Vibration API]</td><td>[http://www.w3.org/2009/dap/ Device API]</td><td class="low">Working draft</td><td class="low">Early draft</td><td class="low">[http://dev.w3.org/2009/dap/vibration/ Updated regularly]</td><td class="low">Experimental implementations</td><td class="low">None</td></tr>
<tr><th>Intent-based events</th><td>N/A</td><td>[http://www.w3.org/2010/webevents/ Web Events Working Group]</td><td class="low">N/A</td><td class="low">Not started</td><td class="low">Not started</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Notification</th><td>[http://www.w3.org/TR/notifications/ Web Notifications]</td><td>[http://www.w3.org/2010/web-notifications/ Web Notifications Working Group]</td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/2006/webapi/WebNotifications/publish/Notifications.html Regularly updated]</td><td class="low">A few experimental ones</td><td class="low">None</td></tr>
<tr><th>System beeps</th><td>N/A</td><td>[http://www.w3.org/2009/dap/ Device API]</td><td class="low">N/A</td><td class="low">Not started</td><td class="low">Not started</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Speech-based interactions</th><td>N/A</td><td>[http://www.w3.org/2005/Incubator/htmlspeech/ HTML Speech Incubator Group], planning to request creation of standards-track work</td><td class="low">N/A</td><td class="low">N/A</td><td>[http://www.w3.org/2005/Incubator/htmlspeech/live/draft-20110203-requirements.html Use cases and requirements]</td><td class="low">N/A</td><td class="low">N/A</td></tr>
<tr><th>Model-based user interfaces</th><td>N/A</td><td>[http://www.w3.org/2011/mbui/ Model-Based User Interfaces Working Group]</td><td class="low">N/A</td><td class="low">N/A</td><td>[http://www.w3.org/2005/Incubator/model-based-ui/XGR-mbui-20100504/ Model-based UI Incubator Group report]</td><td class="low">N/A</td><td class="low">N/A</td></tr>
<tr>
<th rowspan="2">Accessibilitiy</th>
<td>[http://www.w3.org/TR/mwbp-wcag/ <cite>Relationship between Mobile Web Best Practices (MWBP) and Web Content Accessibility Guidelines (WCAG)</cite>]</td>
<td>Mobile Web Best Practices Working Group &amp; Education and Outreach Working Group</td>
<td class="high">Working Group Note</td>
<td class="high">Finished</td>
<td>N/A</td>
<td>N/A</td>
<td>N/A</td>
</tr>
<tr>
<td><cite>[http://www.w3.org/TR/wai-aria/ Accessible Rich Internet Applications (WAI-ARIA) 1.0]</cite></td>
<td>[http://www.w3.org/WAI/PF/ Protocols &amp; Formats Working Group]</td>
<td class="high">Candidate Recommendation</td>
<td class="high">Stable</td>
<td>[http://www.w3.org/WAI/PF/aria/ Last updated Jan 2011]</td>
<td class="medium">Growing deployment</td>
<td class="low">N/A</td>
</tr>
</table>

== Data storage ==
<p>A critical component of many applications is the ability to save state, export content, as well as integrate data from other files and services on the system.</p>
<p>For simple data storage, the <cite><strong>[http://dev.w3.org/html5/webstorage/ Web Storage]</strong></cite> specification offers two basic mechanisms, <code>localStorage</code> and <code>sessionStorage</code>, that can preserve data respectively indefinitely, or on a browser-session basis.</p>
<p>For richer interactions, the Web platform has a growing number of APIs to interact with a device filesystem: the <cite><strong>[http://dev.w3.org/2006/webapi/FileAPI/ File Reader API]</strong></cite> makes it possible to load the content of a file, the <cite><strong>[http://dev.w3.org/2009/dap/file-system/file-writer.html File Writer API]</strong></cite> allows to save or modify a file, while the nascent <strong>[http://dev.w3.org/2009/dap/file-system/file-dir-sys.html FileSystems API]</strong> give access to more general file operations, including directory management.</p>
<p>On top of this file-based access, the <cite><strong>[http://dvcs.w3.org/hg/IndexedDB/raw-file/tip/Overview.html Indexed Database API]</strong></cite> defines a database of values and hierarchical objects that integrates naturally with JavaScript, and can be queried and updated very efficiently. Note that the work around a client-side SQL-based database, which had been started in 2009, has been abandoned in favor of this new system.</p>

<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Simple data storage</th><td>[http://www.w3.org/TR/webstorage/ Web Storage]</td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="high">Candidate Recommendation</td><td class="high">Stable</td><td>[http://dev.w3.org/html5/webstorage/ Updated regularly]</td><td class="high">Well deployed</td><td class="low">None</td></tr>
<tr><th>File reading</th><td>[http://www.w3.org/TR/FileAPI/ File API]</td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft</td><td class="medium">Stabilizing toward LC</td><td>[http://dev.w3.org/2006/webapi/FileAPI/ Regular updates]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>File writing</th><td><cite>[http://www.w3.org/TR/file-writer-api/ File API: Writer]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft</td><td class="low">Early draft (but starting to stabilize)</td><td>[http://dev.w3.org/2009/dap/file-system/file-writer.html Last update May 2011]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>Filesystems operations</th><td><cite>[http://www.w3.org/TR/file-system-api/ File API: Directories and System]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/2009/dap/file-system/file-dir-sys.html Last update May 2011]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th rowspan="2">Database query/update</th><td><cite>[http://www.w3.org/TR/IndexedDB/ Indexed Database API]</cite></td><td rowspan="2">[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td  class="low">Working Draft</td><td class="low">Still changing, but starting to stabilize</td><td>[http://dvcs.w3.org/hg/IndexedDB/raw-file/tip/Overview.html Regularly updated]</td><td class="low">Very limited (?)</td><td class="low">None</td></tr>
<tr><td>[http://www.w3.org/TR/webdatabase/ Web SQL API]</td><td class="low">Working Group Note</td><td class="low">Abandoned</td><td class="low">N/A</td><td>Somewhat deployed, but won’t be further deployed</td><td class="low">N/A</td></tr>
</table>

== Personal Information Management ==

<p>Applications can benefit from integrating with existing data records; on mobile devices, the address book and calendar are particularly useful source of information, which the <cite><strong>[http://dev.w3.org/2009/dap/contacts/ Contacts API]</strong></cite> and the <cite><strong>[http://dev.w3.org/2009/dap/calendar/ Calendar API]</strong></cite> bring access to.</p>


<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Address book data</th><td>[http://www.w3.org/TR/contacts-api/ Contacts API]</td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="medium">Last Call Working Draft</td><td class="low">Stabilizing</td><td>[http://dev.w3.org/2009/dap/contacts/ Regularly updated]</td><td class="low">Very limited</td><td class="low">[http://w3c-test.org/dap/contacts/tests/ early draft]</td></tr>
<tr><th>Calendar data</th><td>[http://www.w3.org/TR/calendar-api/ Calendar API]</td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td class="low">Still changing</td><td>[http://dev.w3.org/2009/dap/calendar/ Regularly updated]</td><td class="low">Very limited</td><td class="low">None</td></tr>

</table>

== Sensors and hardware integration ==

<p>Mobile devices are packed with sensors, making them a great bridge between the real and virtual worlds: GPS, accelerometer, ambient light detector, microphone, camera, thermometer, etc.</p>

<p>To take full advantage of these sensors in mobile Web applications, Web developers need to be provided with hooks to interact with them.</p>

<p>The <cite><strong>[http://dev.w3.org/geo/api/spec-source.html Geolocation API]</strong></cite> provides a common interface for locating the device, independently of the underlying technology (GPS, WIFI networks identification, triangulation in cellular networks, etc.) The [http://www.w3.org/TR/geolocation-API-v2/ second version of that API] adds the ability to retrieve a civic address matching the user’s current location.</p>

<p>Work has also started on providing access to orientation and acceleration data via the <cite><strong>[http://dev.w3.org/geo/api/spec-source-orientation.html DeviceOrientation Event Specification]</strong></cite>.</p>

<p>A new proposed <cite><strong>[http://dev.w3.org/2009/dap/system-info/Sensors.html Sensor API]</strong></cite> (replacing a feature previously available in the abandoned <cite>[http://dev.w3.org/2009/dap/system-info/ System Information API]</cite>) proposes a generic API to get and monitor data from sensors.</p>

<p>As already mentioned in the section on [[#Multimedia]], there is ongoing work on APIs to open up access to camera and microphone streams.</p>
<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th rowspan="2">Geolocation</th><td><cite>[http://www.w3.org/TR/geolocation-API/ Geolocation API]</cite></td><td rowspan="2">[http://www.w3.org/2008/geolocation/ Geolocation Working Group]</td><td class="high">Candidate Recommendation</td><td class="high">Mostly finished</td><td>[http://dev.w3.org/geo/api/spec-source.html Regularly updated]</td><td class="high">Widely deployed</td><td class="medium">[http://dev.w3.org/geo/api/test-suite/Overview.html Good coverage]</td></tr>
<tr><td><cite>[http://www.w3.org/TR/geolocation-API-v2/ Geolocation API v2]</cite></td><td class="medium">Last Call Working Draft</td><td class="low">Still changing</td><td>[http://dev.w3.org/geo/api/spec-source-v2.html Last update Oct 2011]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><th>Accelerometer / Orientation</th><td><cite>[http://www.w3.org/TR/orientation-event/ DeviceOrientation Event Specification]</cite></td><td>[http://www.w3.org/2008/geolocation/ Geolocation Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/geo/api/spec-source-orientation.html Regularly updated]</td><td class="low">Limited, but growing</td><td class="low">None</td></tr>
<tr><th>Battery Status</th><td><cite>[http://www.w3.org/TR/battery-status/ Battery Status API]</cite></td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/2009/dap/system-info/battery-status.html Updated regularly]</td><td class="low">Experimental implementations</td><td class="low">None</td></tr>
<tr><th>Generic sensors</th><td><cite>Sensor API</cite></td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">N/A</td><td class="low">Very early draft</td><td>[http://dev.w3.org/2009/dap/system-info/Sensors.html Last update Nov 2011]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Camera &amp; Microphone streams</th><td><cite>[http://www.w3.org/TR/webrtc/ WebRTC 1.0: Real-time Communication Between Browsers]</cite></td><td>[http://www.w3.org/2011/04/webrtc/ Web Real-Time Communications Working Group]</td><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://dev.w3.org/2011/webrtc/editor/webrtc.html Last updated Aug 23rd]</td><td class="low">A few experimental ones</td><td class="low">None</td></tr>


</table>

== Network ==

<p>Network connectivity represents a major asset for mobile devices: the Web is an immense store of content, as well as an almost endless source of processing power, overcoming two of the limitations of mobile devices.</p>

<p>The Web platform is growing a number of APIs that facilitate establishing network connectivity in different contexts.</p>

<p><cite><strong>[http://dev.w3.org/2006/webapi/XMLHttpRequest/ XMLHttpRequest]</strong></cite> (the “X” in AJAX) is a widely deployed API to load content from Web servers using the HTTP and HTTPs protocol: the W3C specification (formerly known as <cite>XMLHttpRequest Level 2</cite>) completes the existing deployed API with the ability to make requests on servers in a different domain, programmatic feedback on the progress of the network operations, and more efficient handling of binary content. The work on documenting the currently deployed API (XMLHttpRequest Level 1) has been abandoned in favor of getting the new API developed more quickly.</p>

<p>By default, browsers do not allow to make request across different domains (or more specifically, across different <em class="def">origins</em>, a combination of the protocol, domain and port) from a single Web page; this rule protects the user from having a Web site abusing their credentials and stealing their data on another Web site. Sites can opt-out of that rule by making use of the <cite><strong>[http://dev.w3.org/2006/waf/access-control/ Cross-Origin Resource Sharing]</strong></cite> mechanism, opening up much wider cooperation across Web applications and services.</p>

<p>XMLHttpRequest is useful for client-initiated network requests, but mobile devices with their limited network capabilities and the cost that network requests induce on their battery (and sometimes on their users bill) can often make better use of server-initiated requests. The <cite><strong>[http://dev.w3.org/html5/eventsource/ Server-Sent Events]</strong></cite> API allows to trigger DOM events based on push notifications (via HTTP and other protocols.)</p>

<p>The <cite><strong>[http://dev.w3.org/html5/websockets/ WebSocket API]</strong></cite>, built on top of the IETF <cite>[http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-05 WebSocket protocol]</cite>, offers a bidirectional, more flexible, and less resource intensive network connectivity than XMLHttpRequest.</p>

<p>Of course, an important part of using network connectivity relies on being able to determine if such connectivity exists, and the type of network available. The [http://dev.w3.org/html5/spec/offline.html#event-online HTML5 <strong>onLine DOM flag</strong>] (and its associated change event, <code>ononline</code>) signals when network connectivity is available to the Web environment.</p>

<p>The [http://dev.w3.org/2009/dap/netinfo/ <strong>network-information API</strong>] addresses discovery of the network characteristics, allowing to determine for instance if the user is on a WIFI or a 3G connection.</p>
<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>HTTP(s) network API</th><td><cite>[http://www.w3.org/TR/XMLHttpRequest/ XMLHttpRequest]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft</td><td class="low">Still changing, but starting to stabilize</td><td>[http://dev.w3.org/2006/webapi/XMLHttpRequest-2/ Regularly updated]</td><td class="medium">Very broad for level 1 features, limited for level 2</td><td class="low">[http://w3c-test.org/webapps/XMLHttpRequest/tests/ Coverage of XMLHTTPRequest "level 1"]</td></tr>
<tr><th>Cross-domain requests</th><td><cite>[http://www.w3.org/TR/cors/ Cross-Origin Resource Sharing]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft<td class="low">Close to stabilizing</td><td>[http://dev.w3.org/2006/waf/access-control/ Last update November 2011]</td><td class="medium">Growing deployment [http://www.w3.org/Security/wiki/Comparison_of_CORS_and_UM#Implementation_Data Implementation data]</td><td class="low">None (?)</td></tr>
<tr><th>Server-pushed requests</th><td><cite>[http://www.w3.org/TR/eventsource/ Server-Sent Events]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="medium">Working Draft</td><td class="medium">Still changing but stabilizing</td><td>[http://dev.w3.org/html5/eventsource/ Regularly updated]</td><td class="medium">Growing</td><td class="low">None (?)</td></tr>
<tr><th>Bidirectional connections</th><td><cite>[http://www.w3.org/TR/websockets/ The WebSocket API]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="high">Candidate Recommendation</td><td class="high">Stable</td><td>[http://dev.w3.org/html5/websockets/ Regularly updated]</td><td class="medium">Growing</td><td class="low">None</td></tr>
<tr><th>on-line state</th><td>[http://www.w3.org/TR/html5/offline.html#browser-state <cite>HTML5</cite> onLine DOM state]</td><td>[http://www.w3.org/html/wg/ HTML Working Group]</td><td class="medium">Last Call Working Draft</td><td class="high">Mostly stable</td><td>[http://dev.w3.org/html5/spec/offline.html#event-online regularly updated]</td><td class="medium">Getting deployed</td><td class="low">None</td></tr>
<tr><th>Network characteristics</th><td><cite>[http://www.w3.org/TR/netinfo-api/ The Network Information API]</cite></td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td>Early draft</td><td>[http://dev.w3.org/2009/dap/netinfo/ Regularly updated]</td><td class="low">Very limited</td><td class="low">N/A</td></tr>


</table>

== Communication and Discovery ==

<p>Beyond connection to on-line services, allowing communications between users, but also between devices and between applications is an important aspect of a good mobile development platform. To communicate with unknown devices or pre-existing services, a discovery component is critical.</p>

<p>The <cite><strong>[http://dev.w3.org/2009/dap/messaging/ Messaging API]</strong></cite> completes the existing ability to create and send message through links (with <code>sms:</code>, <code>mms:</code> and <code>mailto:</code> URI schemes) with more control on adding attachments and the success of the message sending.</p>

<p>The <code><strong>postMessage</strong></code> API of <cite>[http://dev.w3.org/html5/postmsg/ HTML5 Web Messaging]</cite> allows for Web Applications to communicate between each other.</p>

<p>Exploratory work in the Device APIs Working Group, based on <cite>[http://webintents.org/ Web Intents]</cite>, should also open up possibilities of closer integration of Web applications, as well as of Web applications with native applications.</p>

<p>The recent launch of the <strong>[http://www.w3.org/2011/04/webrtc/ Web Real-Time Communications Working Group]</strong> is the starting point of a much wider set of communication opportunity:</p>
<ul>
<li><strong>Peer-to-peer connection</strong> across devices,</li>
<li><strong>P2P Audio and video streams</strong> allowing for real-time communications between users.</li>
</ul>

<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Emails, SMS and MMS with generated attachments</th><td><cite>[http://www.w3.org/TR/messaging-api/ The Messaging API]</cite></td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="low">Working Draft</td><td class="low">Candidate for replacement by a Web Intents-approach</td><td>[http://dev.w3.org/2009/dap/messaging/ Last update July 2011]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Inter-app communications</th><td><cite>[http://www.w3.org/TR/webmessaging/ HTML5 Web Messaging]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Working Draft</td><td class="low">Stabilizing</td><td>[http://dev.w3.org/html5/postmsg/ Regularly updated]</td><td class="low">Limited (?)</td><td class="low">None</td></tr>
<tr><th>Inter-app triggers</th><td>Web Intents</td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group] (expected to form a task force with Web Apps Working Group)</td><td class="low">N/A</td><td class="low">Not started</td><td>Starting from [http://webintents.org/ Web Intents]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>P2P connections</th><td rowspan="2"><cite>[http://www.w3.org/TR/webrtc/ WebRTC 1.0: Real-time Communication Between Browsers]</cite></td><td rowspan="2">[http://www.w3.org/2011/04/webrtc/ Web Real-Time Communications Working Group]</td><td  rowspan="2" class="low">Working Draft</td><td rowspan="2" class="low">Early draft</td><td rowspan="2">[http://dev.w3.org/2011/webrtc/editor/webrtc.html Regularly updated]</td><td rowspan="2" class="low">None</td><td rowspan="2" class="low">None</td></tr>
<tr><th>P2P Video/Audio streams</th></tr>

</table>

== Packaging ==

<p>An important aspect of the user experience of applications is linked to how the user perceives the said application is available permanently (even when off-line, which is particularly important on mobile devices), as well as how it can shared and distributed, typically through purchases via applications stores — this is adequately addressed by packaging the application.</p>

<p>The Web platform offers two complementary approaches to packaging Web applications:</p>
<ul>
<li>HTML5’s <code><strong>[http://dev.w3.org/html5/spec/offline.html#appcache ApplicationCache]</strong></code> enables access to Web applications off-line through the definition of a manifest of files that the browser is expected to keep in its cache;</li>
<li>the <strong>[http://www.w3.org/standards/techs/widgets W3C Widgets]</strong> family of specifications define a framework for distributing Web applications as Zip files completed by a configuration file (see <cite>[http://www.w3.org/TR/widgets/ Widget Packaging and Configuration]</cite>); this configuration file is the basis for additional features such as [http://www.w3.org/TR/widgets-digsig/ signature of applications] , controlled access to advanced APIs, [http://www.w3.org/TR/widgets-access/ restricted network usage], etc.</li>
</ul>


<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th>Application Cache</th><td>[http://www.w3.org/TR/html5/offline.html#appcache <cite>HTML5</cite> Application Cache]</td><td>[http://www.w3.org/html/wg/ HTML Working Group]</td><td class="medium">Last Call Working Draft</td><td class="low">Still changing but stabilizing</td><td>[http://dev.w3.org/html5/spec/offline.html#offline Regularly updated]</td><td class="medium">Getting deployed</td><td class="low">None</td></tr>
<tr><th rowspan="3">Widgets</th><td>[http://www.w3.org/TR/widgets/ Widgets Packaging &amp; Configuration]</td><td rowspan="3">[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="high">Recommendation</td><td class="high">Finished</td><td>[http://dev.w3.org/2006/waf/widgets/ Last update Aug 2011]</td><td class="low">[http://dev.w3.org/2006/waf/widgets/imp-report/ 4 complete implementations; 1 impl 99%]</td><td class="high">[http://dev.w3.org/2006/waf/widgets/test-suite/ Full coverage]</td></tr>
<tr><td><cite>[http://www.w3.org/TR/widgets-digsig/ Digital Signatures for Widgets]</cite></td><td class="high">Proposed Recommendation</td><td class="high">Mostly finished</td><td>[http://dev.w3.org/2006/waf/widgets-digsig/ Last update Aug 2011]</td><td class="low">Limited</td><td class="high">[http://dev.w3.org/2006/waf/widgets-digsig/test-suite/ Full coverage]</td></tr>
<tr><td><cite>[http://www.w3.org/TR/widgets-access/ Widget Access Request Policy] (WARP)</cite></td><td class="high">Candidate Recommendation</td><td class="high"></td><td>[http://dev.w3.org/2006/waf/widgets-access/ Last update Aug 2011]</td><td class="low">[http://dev.w3.org/2006/waf/widgets-access/imp-report/ 3 complete implementations; 1 impl 98%]</td><td class="high">[http://dev.w3.org/2006/waf/widgets-access/test-suite/ Full coverage]</td></tr>

</table>

== Performance &amp; Optimization ==

<p>Due to their limited CPU, and more importantly to their limited battery, mobile devices require a lot of attention in terms of performance.</p>

<p>The work started by the [http://www.w3.org/2010/webperf/ Web Performance Working Group] on <cite><strong>[http://w3c-test.org/webperf/specs/NavigationTiming/ Navigation Timing]</strong></cite>, <cite><strong>[http://w3c-test.org/webperf/specs/ResourceTiming/ Resource Timing]</strong></cite>, and more recently <cite><strong>[http://dvcs.w3.org/hg/webperf/raw-file/tip/specs/PerformanceTimeline/Overview.html Performance Timeline]</strong></cite> and <cite><strong>[https://dvcs.w3.org/hg/webperf/raw-file/tip/specs/UserTiming/Overview.html User Timing]</strong></cite>, gives tools to Web developers for optimizing their Web applications. </p>

<p>The proposed work on [http://w3c-test.org/webperf/specs/setImmediate/ Efficient Script Yielding] offers the opportunity to Web developers to use more efficiently asynchronous programming.</p>

<p>The [http://www.w3.org/TR/page-visibility/ API to determine whether a Web page is being displayed] (<cite><strong>Page Visibility API</strong></cite>) can also be used to adapt the usage of resources to the need of the Web application, for instance by reducing network activity when the page is minimized. Likewise, the [http://www.w3.org/TR/animation-timing/ Timing control for script-based animations API] can help reduce the usage of resources needed for playing animations.</p>

<p>The [http://dev.w3.org/2009/dap/system-info/battery-status.html battery API] allows to adjust the use of resources to the current level of power available in the battery of a mobile device.</p>

<p>Beyond optimization of resources, the perceived reactivity of an application is also a critical aspect of the mobile user experience. The <strong>thread-like mechanism</strong> made possible via <cite>[http://dev.w3.org/html5/workers/ Web Workers]</cite> allows keeping the user interface responsive by offloading the most resource-intensive operations into a background process.</p>

<p>The <cite>[http://www.w3.org/TR/mwabp/ Mobile Web Application Best Practices]</cite> provide general advice on how to build Web applications that work well on mobile devices, taking into account in particular the needs for optimization.</p>


<table class="simple" border="1">

<tr><th>Feature</th><th>Specification</th><th>Working Group</th><th>Maturity</th><th>Stability</th><th>Latest editors draft</th><th>Current implementations</th><th>Test suite</th></tr>
<tr><th rowspan="4">Timing hooks</th><td>[http://www.w3.org/TR/navigation-timing/ Navigation Timing]</td><td rowspan="7">[http://www.w3.org/2010/webperf/ Web Performance Working Group]</td><td class="high">Candidate Recommendation</td><td class="high">Mostly finished</td><td>[http://w3c-test.org/webperf/specs/NavigationTiming/ Regularly updated]</td><td class="medium">Getting deployed</td><td class="low">[http://w3c-test.org/webperf/tests/ Started]</td></tr>
<tr><td>[http://www.w3.org/TR/resource-timing/ Resource timing]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://www.w3c-test.org/webperf/specs/ResourceTiming/ Regularly updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><td>[http://www.w3.org/TR/performance-timeline/ Performance Timeline]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://www.w3c-test.org/webperf/specs/PerformanceTimeline/ Regularly updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><td>[http://www.w3.org/TR/user-timing/ User timing]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://www.w3c-test.org/webperf/specs/UserTiming/ Regularly updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><th>Priority handling</th><td>Efficient Script Yielding</td><td class="low">N/A</td><td class="low">Early draft</td><td>[http://w3c-test.org/webperf/specs/setImmediate/ Regulary updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><th>Page Visibility detection</th><td><cite>[http://www.w3.org/TR/page-visibility/ Page visibility API]</cite><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://www.w3c-test.org/webperf/specs/PageVisibility/ Regularly updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><th>Animation optimization</th><td><cite>[http://www.w3.org/TR/animation-timing/ Timing control for script-based animations]</cite><td class="low">Working Draft</td><td class="low">Early draft</td><td>[http://w3c-test.org/webperf/specs/RequestAnimationFrame/ Regularly updated]</td><td class="low">None</td><td class="low">N/A</td></tr>
<tr><th>Threading</th><td><cite>[http://www.w3.org/TR/workers/ Web Workers]</cite></td><td>[http://www.w3.org/2008/webapps/ Web Applications Working Group]</td><td class="low">Last Call</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/html5/workers/ Regularly updated]</td><td class="medium">Growing</td><td class="low">None</td></tr>
<tr><th>Battery Status</th><td><cite>[http://www.w3.org/TR/battery-status/ Battery Status Events]</cite></td><td>[http://www.w3.org/2009/dap/ Device APIs Working Group]</td><td class="medium">Last Call Working Draft</td><td class="medium">Stabilizing</td><td>[http://dev.w3.org/2009/dap/system-info/battery-status.html Updated regularly]</td><td class="low">None</td><td class="low">None</td></tr>
<tr><th>Optimization Best Practices</th><td><cite>[http://www.w3.org/TR/mwabp/ Mobile Web Application Best Practices]</cite></td><td>[http://www.w3.org/2005/MWI/BPWG/ Mobile Web Best Practices Working Group] (now closed)</td><td class="high">Standard</td><td class="high">Finished</td><td>N/A</td><td>N/A</td><td>N/A</td></tr>

</table>