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cpeikert There are roughly five ways to install apps: Google Play Store, F-Droid, Aurora, directly from the developers (e.g. from Github), or through alternative web stores like APKMirror. Aurora downloads apps from the Play Store, but without the need to log in. Furthermore, you can use Obtanium to ensure that apps from Github, for example, are updated automatically. I use Obtanium for apps that are reputable like Signal and Protonmail, and the Play Store for apps that are not offered in a secure alternative way, like my banking app. Side of Burritos made a nice video on how to use the Play Store in a private way on GrapheneOS. F-droid is nice and easy to use for installing open-source apps, but it has some security issues, which have been discussed several times on this forum.