Android's built-in backup mechanism, which relies on the Google Play Services framework, can backup contacts, call history, text messages, and certain application data and device settings to users’ individual Google Drive accounts. However, backing up and restoring apps can be a pain, especially when you switch between phones from different OEMs or prefer to use a custom ROM without any Google apps. The Mountain View giant may be removing the fan-favorite ADB backup and restore tool, which means users have to opt for root-only tools for better backups. In light of these concerns, the developers over at LineageOS have chosen SeedVault as its default backup solution.

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For those not familiar with SeedVault, it is an open-source backup app that uses the same internal APIs as adb backup. The application doesn't need root access, but it must be compiled with the operating system. The backup location is user-configurable, with options ranging from a USB flash drive to a remote self-hosted cloud alternative such as NextCloud. This makes SeedVault a particularly viable option for users who doesn't want to store their personal data to Google's proprietary cloud-based storage.

All the backup contents created by SeedVault are encrypted by client-side encryption (AES/GCM/NoPadding), which is unlockable with a 12-word randomly-generated key compliant with the BIP39 standard. Moreover, power users have the freedom to decrypt, inspect, and re-encrypt their backups through an external standalone utility.

Below you can catch a glimpse of SeedVault in action. Note that the tweet was posted long before the app made its way to LineageOS, thus some UI elements might be different from the current implementation.

The source code of the LineageOS version of SeedVault can be found here. With the addition of more contributors who can maintain or port the backup solution to different Android forks, we are hoping to see the list of SeedVault-supported custom ROMs grow in the coming days.

Thanks to XDA Senior Member kurtn for the tip!