How WCAG 2.0 Can Enhance Usability
for Users of Mobile Devices

WCAG requires a text equivalent for all non-text content, including images. This enables users in the mobile context to read content without downloading images.

Mobile devices are often used in situations with significant background noise that makes it difficult to hear the audio track of multimedia content. It public places it may be socially unacceptable to listen to the soundtrack. Captions enable the user to understand the multimedia content in these situations.

Unlikely to provide any additional benefit (if audio description is supported by device, might conceivably help with understanding video on small screen)

Refer to SC 1.2.1 Captions (Prerecorded).

Refer to 1.2.2 Audio Description or Full Text Alternative in this document.

Refer to SC 1.2.2 Audio Description or Full Text Alternative in this document.

Refer to SC 1.2.2 Audio Description or Full Text Alternative in this document.

It allows change and transformation of content in a more flexible way to suit each device.

Many mobile devices have monochrome screens, often do not have good color contrast and are often used in less-than-ideal lighting conditions, and so like non-visual users or those with colour perception deficit they may be unable to percieve information conveyed by colour. This success criterion ensures that users who cannot perceive colour correctly for whatever reason will be able to understand and operate the content.

Mobile devices may have monochrome screens. Users in a mobile context may view the screen in unfavorable lighting conditions. Adequate color contrast will also help these users.

Providing options within the content to switch between layouts that use a variety of font sizes may make for a better experience for users with small screens.

Text is more easily adapted to suit the diverse needs of different devices.

Refer to success criterion 1.4.3 Contrast (Minimum).

Flexibility of presentation helps to ensure that adapted content will be easier to read.

Refer to SC 1.4.5 Images of Text (Limited).

Mobile devices typically lack a pointing device and therefore this success criterion benefits the typical user regardless of disability.

Mobile users typically navigate using the keypad. Becoming trapped by any component on a page would make it impossible to use the content.

The description under 2.1.1 Keyboard is applicable.

Content that moves, scrolls or auto-updates may be difficult to see with the reduced size of the mobile viewport. Blinking text may be especially difficult to see on the small screen and in poor lighting conditions.

Mobile users typically navigate using the keypad. This can result in a large number of keystrokes to reach the main content of a page, especially if it is preceded by extensive navigation menus or lists of links. This SC also helps users skip large blocks of navigation links at the top of a page, a problem described in NAVBAR.

Like users with no vision or limited field of vision, or cognitive disability, mobile users with small screens may have difficulty scanning and summarizing the overall content of a page. Perhaps the most useful item of metadata for a page is a descriptive page title, to provide a quick description of the content of a page.

Mobile users are unlikely to have a pointing device so keypad is the primary means of navigation, making focus order especially important.

Users of mobile devices may suffer undue delay and cost as a result of following links due to network charges and device limitations, so it is important to inform them of the purpose of each link.

No added benefit.

Mobile device users typically navigate with the keypad, so if supported, this would make for easier navigation on small displays with poor visibility.

Refer to 2.4.4 Link Purpose (In Context). Refer to “Link text not descriptive” in Summary of Experience of Content Features by Users section.

Section headings allow ...easier adaptation of content where it needs to be divided into several pages, as well as potentially facilitating access to the sections of the document that a user is interested in.

Change of user agent: Using a mobile device, launching a new application to render content is especially heavy on processor usage and battery life and should be avoided unless the user has requested it. Change of viewport: Many mobile devices cannot support more than one window and consequently, attempting to open one will have unpredictable results. Even where mobile devices do support multiple windows, their use is especially problematic. Opening new windows when an element receives focus is especially difficult for the mobile user. Change of focus: Navigation may be especially difficult with a reduced keyboard, and the reduced viewport of the mobile device may lead to the visual user becoming disoriented. Change of content: Auto-refreshing pages ... In a mobile environment they may expose the user to undue cost as a result of such a page being left open or put unnoticed into the background. also While redirection is a commonly employed mechanism, it must be remembered that redirection usually requires a round-trip to the browser. This adds to delay on slow links...

In much the same way as 3.2.1 On Focus.

In much the same way as 3.2.1 On Focus.

Content adaptation and small screens may result in the visual relationship between labels and controls becoming lost. An explicit association enables the user agent to render them as intended.

Mobile user agents are very diverse and it is not possible to be sure that they will behave as expected if invalid markup is used.

Similar to the benefit described for 3.3.2 Labels or Instructions but applicable to all user interface components. When the name, role, value, state, and properties is defined this potentially enables reformatting and transformation for the mobile context.