Google has released the second Developer Preview for Android 13, and it includes a big change in how the platform delivers alerts. Apps built for Android 13 will need to ask for permission before they can send notifications. Apps made for Android 12 or lower won't face this obligation, but this could still be very helpful if you're tired of having to disable notifications for apps that enable them by default.
Developers, meanwhile, can establish "downgradeable" permissions that scale back once they're no longer required. An app that needed access to your location before might switch it off if a relevant feature was disabled, or if the permission is no longer necessary in Android 13.
After that, Developer Preview 2's biggest upgrades mostly apply to audio. You'll find Bluetooth LE Audio support that promises "high fidelity" sound without a big hit to battery life. Musicians will find MIDI 2.0 compatibility that lets you use higher-resolution and more expressive USB instruments. The newer Android 13 build is also better at handling non-Latin languages like Japanese and Tamil.
You'll need a Pixel 4, Pixel 4a or newer Google phone to load the Android 13 DP2 system image outside of an emulator. As with past previews, you won't want to install this on your main phone — there are likely to be plenty of remaining glitches and compatibility headaches. Google is still targeting platform stability between June and July, and the polished release isn't due until sometime after that. If you can afford to experiment, though, it should be clear the new OS is quickly taking shape.