android_webview/docs/channels.md - chromium/src.git - Git at Google

 # Understanding WebView Channels

 Since the introduction of WebView as an updatable APK in Android L, WebView has
 had some conception of pre-release channels. The details of the implementation
 of these channels has differed between different generations of WebView, and
 this document explains those details.

 [TOC]

 ## Standalone WebView (Android L - M)

 The pre-release channels strategy of Chrome for Android has been to build
 separate APKs, each with a unique package name, so that they can be installed
 side-by-side. In contrast, Standalone WebView has only a single package name
 (com.google.android.webview) that is recognized by Android as a valid WebView
 provider, and instead utilizes [the "tracks"
 API](https://developers.google.com/android-publisher/tracks) provided by Google
 Play. This allows users to opt-in to beta updates, but users cannot have
 simultaneous installations of both stable and beta Standalone WebView on a
 single device.

 All users that have Android System WebView installed and enabled are eligible to
 receive updates published to the production track. In addition, users can opt-in
 to the beta track by [joining the beta tester
 program](/android_webview/docs/prerelease.md#android-l-or-m-plus-all-versions-of-android-without-chrome).
 Once a user's account is in the beta program, it is eligible to receive updates
 that have been published to the beta track. The Play Store updates users to the
 APK with the highest `versionCode` among eligible tracks.

 Google publishes an APK of Android System WebView to the beta track based on the
 [same release cycle](https://chromiumdash.appspot.com/schedule) as Chrome Beta.

 Similarly, builds of Chrome for "Dev" channel releases include a build of
 WebView which gets published to an alpha track. Only users belonging to specific
 internal Google groups are eligible for Play Store updates from Android System
 WebView alpha track, including members of Google's internal Chrome for Android
 and Android WebView teams.

 ### Changes in version 75.0.3770.40

 Prior to version 75, WebView's internal logic had no way of knowing whether it
 had been built for a dev, beta, or stable release. Beginning with version
 75.0.3770.40, Google builds separate APKs for each of stable, beta, and dev
 channels, with the internal logic differing only in that it is aware of which
 channel it was built for.

 This change allows for different logic flow depending on the channel, such as
 sampling crash reports differently, targeting beta users for experiments, etc.

 With this change, the WebView APKs belonging to the three different channels
 were given [unique `versionCode` values](/build/util/android_chrome_version.py),
 with stable having a final digit of 0, beta a final digit of 1, and dev 2.
 Having identical package names required unique versionCodes for the different
 channel builds to exist simultaneously on platforms like Google Play and
 Google's internal crash and performance analytics infrastructure. These specific
 values were chosen so that a user who has opted into the beta program will still
 receive the beta APK (Play Store delivers the APK with the higher `versionCode`
 value) even if a stable APK from the same build is available (such as when we
 promote a beta build to stable), so that the user can receive beta-targeted
 experiments.

 To avoid conflicting with [Trichrome WebView's pre-release channel
 strategy](#trichrome-android-q), Standalone WebView APKs are given a
 `maxSdkVersion` value of 28, so that users who have opted into the beta program
 described above do not experience the Play Store updating their Trichrome
 WebView stable APK to Standalone WebView beta (since they share the same package
 name).

 ## Monochrome (Android N - P)

 For Android versions N - P, WebView is built as a part of the Chrome APK. Since
 Chrome already supported side-by-side installs of different Chrome channels on
 Android, a menu was added to Android's Developer Options Settings that [allows a
 user to choose](/android_webview/docs/prerelease.md#android-n_o_or-p) which of
 the installed versions of Chrome to use as the WebView.

 ## Trichrome (Android Q+)

 For Android Q+, WebView and Chrome are again separately installed APKs. However,
 Google began building a separate package of WebView for each of the four Chrome
 channels: Stable, Beta, Dev, and Canary. Like with Monochrome, users can find
 each of these four channels of WebView on the Play Store and install them
 simultaneously on a single device. Also like Monochrome, users can use the
 "WebView implementation" menu to choose which installed WebView the system should
 use.

 Trichrome WebView APKs (of all channels) have a `versionCode` value with a final
 digit of 3 ([to match Trichrome Chrome's
 `versionCode`](https://cs.chromium.org/chromium/src/build/util/android_chrome_version.py)).

 Users may choose to opt into the beta program for Android System WebView
 (com.google.android.webview), but it will have no effect on Android Q, as the
 only APK of this package that gets published to the beta track is Standalone
 WebView, which has a `maxSdkVersion` value of 28. While confusing, this helps
 avoid the user's stable WebView installation being updated to beta, since the
 preferred method for using WebView beta on Android Q is installing the separate
 package from the Play Store. Without this, the same package would receive
 updates from the builds of both Trichrome WebView stable (at the time of a
 stable release) and Standalone WebView beta (at the time of a beta promotion).
 Switching back and forth between these generations would involve very large
 update deltas.

 ## See Also

 - [Try out WebView beta](/android_webview/docs/prerelease.md)
 - [Chrome Release
   Channels](https://www.chromium.org/getting-involved/dev-channel)
	# Understanding WebView Channels

	Since the introduction of WebView as an updatable APK in Android L, WebView has
	had some conception of pre-release channels. The details of the implementation
	of these channels has differed between different generations of WebView, and
	this document explains those details.

	[TOC]

	## Standalone WebView (Android L - M)

	The pre-release channels strategy of Chrome for Android has been to build
	separate APKs, each with a unique package name, so that they can be installed
	side-by-side. In contrast, Standalone WebView has only a single package name
	(com.google.android.webview) that is recognized by Android as a valid WebView
	provider, and instead utilizes [the "tracks"
	API](https://developers.google.com/android-publisher/tracks) provided by Google
	Play. This allows users to opt-in to beta updates, but users cannot have
	simultaneous installations of both stable and beta Standalone WebView on a
	single device.

	All users that have Android System WebView installed and enabled are eligible to
	receive updates published to the production track. In addition, users can opt-in
	to the beta track by [joining the beta tester
	program](/android_webview/docs/prerelease.md#android-l-or-m-plus-all-versions-of-android-without-chrome).
	Once a user's account is in the beta program, it is eligible to receive updates
	that have been published to the beta track. The Play Store updates users to the
	APK with the highest `versionCode` among eligible tracks.

	Google publishes an APK of Android System WebView to the beta track based on the
	[same release cycle](https://chromiumdash.appspot.com/schedule) as Chrome Beta.

	Similarly, builds of Chrome for "Dev" channel releases include a build of
	WebView which gets published to an alpha track. Only users belonging to specific
	internal Google groups are eligible for Play Store updates from Android System
	WebView alpha track, including members of Google's internal Chrome for Android
	and Android WebView teams.

	### Changes in version 75.0.3770.40

	Prior to version 75, WebView's internal logic had no way of knowing whether it
	had been built for a dev, beta, or stable release. Beginning with version
	75.0.3770.40, Google builds separate APKs for each of stable, beta, and dev
	channels, with the internal logic differing only in that it is aware of which
	channel it was built for.

	This change allows for different logic flow depending on the channel, such as
	sampling crash reports differently, targeting beta users for experiments, etc.

	With this change, the WebView APKs belonging to the three different channels
	were given [unique `versionCode` values](/build/util/android_chrome_version.py),
	with stable having a final digit of 0, beta a final digit of 1, and dev 2.
	Having identical package names required unique versionCodes for the different
	channel builds to exist simultaneously on platforms like Google Play and
	Google's internal crash and performance analytics infrastructure. These specific
	values were chosen so that a user who has opted into the beta program will still
	receive the beta APK (Play Store delivers the APK with the higher `versionCode`
	value) even if a stable APK from the same build is available (such as when we
	promote a beta build to stable), so that the user can receive beta-targeted
	experiments.

	To avoid conflicting with [Trichrome WebView's pre-release channel
	strategy](#trichrome-android-q), Standalone WebView APKs are given a
	`maxSdkVersion` value of 28, so that users who have opted into the beta program
	described above do not experience the Play Store updating their Trichrome
	WebView stable APK to Standalone WebView beta (since they share the same package
	name).

	## Monochrome (Android N - P)

	For Android versions N - P, WebView is built as a part of the Chrome APK. Since
	Chrome already supported side-by-side installs of different Chrome channels on
	Android, a menu was added to Android's Developer Options Settings that [allows a
	user to choose](/android_webview/docs/prerelease.md#android-n_o_or-p) which of
	the installed versions of Chrome to use as the WebView.

	## Trichrome (Android Q+)

	For Android Q+, WebView and Chrome are again separately installed APKs. However,
	Google began building a separate package of WebView for each of the four Chrome
	channels: Stable, Beta, Dev, and Canary. Like with Monochrome, users can find
	each of these four channels of WebView on the Play Store and install them
	simultaneously on a single device. Also like Monochrome, users can use the
	"WebView implementation" menu to choose which installed WebView the system should
	use.

	Trichrome WebView APKs (of all channels) have a `versionCode` value with a final
	digit of 3 ([to match Trichrome Chrome's
	`versionCode`](https://cs.chromium.org/chromium/src/build/util/android_chrome_version.py)).

	Users may choose to opt into the beta program for Android System WebView
	(com.google.android.webview), but it will have no effect on Android Q, as the
	only APK of this package that gets published to the beta track is Standalone
	WebView, which has a `maxSdkVersion` value of 28. While confusing, this helps
	avoid the user's stable WebView installation being updated to beta, since the
	preferred method for using WebView beta on Android Q is installing the separate
	package from the Play Store. Without this, the same package would receive
	updates from the builds of both Trichrome WebView stable (at the time of a
	stable release) and Standalone WebView beta (at the time of a beta promotion).
	Switching back and forth between these generations would involve very large
	update deltas.

	## See Also

	- [Try out WebView beta](/android_webview/docs/prerelease.md)
	- [Chrome Release
	Channels](https://www.chromium.org/getting-involved/dev-channel)