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Making WebViews Work for the Web
Making WebViews Work for the Web
Dominique Hazael-Massieux
Copyright © 2021 W3C ® (MIT, ERCIM, Keio, Beihang)
Making WebViews Work for the Web
Dominique Hazaël-Massieux, dom@w3.org, @dontcallmeDOM
TPAC 2021
Goal
Identify what role W3C should play in making WebViews work better for the Web
WebViews
Def: Component used in native apps to render content based on Web technologies
Do they matter?
- 80% of native apps use WebViews (on Android?)
- 10+% of Web content is rendered on WebViews (CloudFlare radar) - more than Firefox or Safari iOS
- Key to mini-apps ecosystem (850M users)
More reach for Web Technologies?
Yes, but
- Murky story on security (SPECTRE) and privacy
- Not all Web technologies work there as expected (e.g. permission-based APIs)
- Little awareness and affordance in the Web developer community (analytics, testing)
Usages
- Ad-rendering
- Re-use one's own Web content
- Re-use infrastructure (e.g. login)
- In-app browser (Facebook, Pinterest)
- Context-specific Web content (e.g. TV sets)
- … (no good data on this so far)
Web-Native on 
| WebView | CT | TWA |
| All browser features |
❌
| ✅
| ✅
|
| Default browser |
❌
| ✅
| ✅
|
| Browser storage |
❌
| ✅
| ✅
|
| Native APIs |
✅
| ❌
| ❌
|
| Custom rendering |
✅
| ❌
| ❌
|
| Seamless UI |
✅
| ❌
| ✅
|
| Web-safe |
❌
| ✅
| ✅
|
| Target content |
Curated
| Any
| 🔒Own
|
Web-Native on iOS
| UI | WK | SFView | ASWebAuth |
| All browser features |
❌
| ❌
| ✅
| ?
|
| Default browser |
❌
| ❌
| ❌
| ?
|
| Browser storage |
❌
| ❌
| ✅
| ✅
|
| Native APIs |
✅
| ✅
| ❌
| ?
|
| Custom rendering |
✅
| ✅
| ❌
| ❌
|
| Seamless UI |
✅
| ✅
| ❌
| ✅?
|
| Web-safe |
❌
| ❌
| ✅
| ?
|
| Target content |
Curated
| Curated
| Any
| Auth
|
W3C & WebViews
- MiniApps Working Group
- Intersection with Web Advertizing
- Potential impact on Web API design?
- Giving more control to developers on usage in WebViews? (e.g. via CSP)
- Potential next steps
