here is the intro. need to add links to notes

Hardware Composer Validation

Android 10 adds a new VTS test calss for Hardware Composer validation through the readback interface in IComposerClient.hal. If vendors don't implement readback, test pass automatically.

ASurfaceControl

Android 10 adds ASurfaceControl, a new way for SurfaceFlinger to accept buffers.

OpenGL ES Layers

Android 10 introduces a layering system for GLES.

EGL 1.5

Android 10 implements the EGL 1.5 interface. For information on new features in EGL 1.5, view the Khronos Releases EGL 1.5 Specification.

Performance Refresh Rate

Android 10 adds support for a performance refresh rate. This feature is turned off by default.

Multiuser Backup and Restore

Android 10 supports backup and restore functionality for all users on a device. Previously, backup and restore was only available for the system user. Backup and restore for nonsystem users is turned off by default as it has only partial coverage for settings, wallpaper, and system components.