Google is moving fluidly between broad Android improvements for the upcoming M preview build and more specific improvements for the company's apps and APIs. One of the first reveals was for a new Chrome feature, Chrome Custom Tabs. This is basically a more robust alternative to embedding a web view in an app, adding a minimal and customized window of Google Chrome on top of the active app.
The demo on stage was with Pinterest. When a user clicked on web content a Custom Tab launches instead. This is a minimal Chrome tab that's sort of "stuck" on top of the app itself. The app and the user have access to all of Chrome's rendering capabilities, saved passwords, auto-fill from the keyboard, and all of Chrome's security features.
Chrome Custom Tabs are available to developer build users starting today, and will launch on the stable version of Chrome for Android sometime on the third quarter of this year.