Extras for AA uses Substratum to heavily customize Android Auto’s in-car UI
If you’ve dabbled in custom themes on Android, then the name “Substratum” may ring a bell. The overlay-based theming mechanism dynamically modifies the resources of an app without actually touching the corresponding APK. Such a design makes Substratum an ideal solution to alter the UI elements of apps like Android Auto that otherwise offer very few customization options. In fact, last year we covered a mod that used Substratum theming to change the Android Auto wallpaper.
Gabriele Rizzo, the creator of that mod, has now come up with a new Substratum mod called Extras For AA that helps users customize the in-car user interface of Android Auto to their hearts’ content. From adding/removing the status bar elements to applying custom color accents on the bottom bar — the theme can modify nearly every aspect of the stock Android Auto UI. Hiding the navigation bar altogether is also possible so that you can show apps in full-screen mode. There is even a “Madness Mode” through which you can literally replace the launcher icon with the clock!
Do note that a new Android Auto update may break the theme, which is why it’s recommended you disable the theme first before installing the update, after which you can re-build the theme overlays. In some rare cases, you may have to wait for the developer to push a new build of the theme with the required compatibility patches. The theme itself is open source, and the source code is available on the developer’s GitHub profile.
According to Gabriele (XDA Senior Member shmykelsa), the theme works best with Substratum Lite. The developer also offers a special variant of the theme called Extras For AA Legacy, which is solely meant for devices that can’t run Substratum Lite. The “legacy” variant is still considered beta, though, which means you may face occasional bugs and crashes while using it. In case you have a phone with Android Oreo or higher, you should opt for the normal variant for best compatibility.
Keep in mind that Substratum itself requires root access to work unless your device is still on Android 8 Oreo. That’s because Android doesn’t allow users to apply custom overlays that weren’t signed by them or an OEM. If your device is rooted and you would like to proceed with theming Android Auto, then check out the Extras for AA forum thread linked below or download the app from the Google Play Store.