Android 12’s wallpaper-based themes can be abused to make phones laggy and unusable
Android 12 has a ton of visual changes, the biggest of which is Material You. Material You’s dynamic colors feature makes use of monet, a new theme engine introduced in Android 12 — and currently exclusive to Pixel phones — to extract colors from your wallpaper and generate a rich palette of pastel colors. Apps can then apply these colors to their UIs in various ways, which is what apps that incorporate Material You typically do. However, it turns out you can abuse Material You’s color-changing prowess to slow a phone to a crawl.
Firstly, you’ll need to set up some kind of system to automatically change the wallpaper in the background. I used the “Auto Change Wallpaper” app on the Google Play Store. Install it and import some images into an album. Make sure you then tell it to apply the wallpaper to your lock screen too and set a low time to change wallpapers — something like 10 seconds should do the trick. I tested this on the Google Pixel 6 Pro, and it made my phone borderline unusable. This isn’t the first problem spotted with Material You’s wallpaper theming if you’re using an automatic wallpaper switcher, as it may also be a major problem for gamers.
Now, I know that this is very much an unlikely use case, but it’s something that you can easily do to your smartphone to make it borderline unusable. The only way I was able to fix it was by going to the settings and lagging through the app selection to uninstall the “Auto Change Wallpaper” app. I was trying to pull down the status bar the whole time in the video above, and it took quite a long time for my phone to actually let me pull it down. As well, the Pixel Launcher consistently dies and refuses to work, and the phone itself lags heavily. The Pixel Launcher constantly refreshes to apply the new color theming that the monet engine selected.
All in all, I wouldn’t call it uncommon for someone to want to change their phone’s wallpaper frequently, even if every 10 seconds is somewhat excessive. Given the level of havoc this can cause on a phone (especially if done unknowingly to a friend), though, it’s worth pointing out as a potential flaw in Material You that might cause problems for some people. In case your phone gets too laggy to uninstall the app, I recommend enabling USB debugging before testing this out, just in case you need to uninstall the app using adb. To uninstall the app with adb, simply run the following command:
adb uninstall viet.dev.apps.autochangewallpaper
Make sure to check the package name of the app if you decide to try this out with another app instead.