Beta 1 of Android 15 Prototype Released for Testing Purposes.

Android 15 Beta 1 testing release brings several notable changes:

Apps specifically designed for Android 15 now showcase edge-to-edge display as default. This means that the color and content of the apps will be displayed in a semi-transparent manner below the status bar at the top and the navigation bar at the bottom (refer to the accompanying image).

Text justification is now supported to be displayed flush left and right, with inter-character spacing, catering to languages like Chinese and Japanese.

Support for app archiving now allows backing up app files to the cloud to save storage space, with compatibility at the OS level.

An added API for managing keys enables end-to-end encryption (E2EE) for enhanced security.

Improved handling of bilingual displays on the screen compared to previous versions.

Source: Android Developers

TLDR: Android 15 Beta 1 introduces edge-to-edge display, text justification, app archiving, E2EE encryption support, and better bilingual display compatibility.