If you're into rooting these days, there's a good chance you've at least tried out FlashFire by well-known SuperSU developer Chainfire. It's one of the friendliest tools to use for flashing firmware images and mods, and it can even install official OTAs while keeping root intact. Today, Chainfire is releasing a new version of FlashFire with a pair of new features that will make it even more powerful: it can now create fastboot-flashable backups and there's a new option to preserve the existing recovery after installing OTAs and ZIPs.
FlashFire has long had the ability to create backups, but they could only be restored through a custom recovery or from FlashFire itself. If things didn't go well after a flash, it might take quite a few steps to get a device running again before a backup could be put to use. Today's update to FlashFire answers this issue by giving users the ability to create backups that can be flashed directly from a computer using fastboot. In other words, if you can get into the bootloader, you can probably restore everything to its previous condition... well, sorta.
There are a few important details about backups and limitations, and some of these may change in future releases; but first, Chainfire points out that this feature, like many others in FlashFire, is still deeply experimental and prone to breaking. Let's be honest, if you're using a tool like this, you already know to keep backups of critical files and you're probably prepared to take risks with your devices. If that doesn't sound like you, back away slowly.
The first note about FlashFire's backups is that they are currently limited to the most common partitions: boot, recovery, system, vendor, oem, cache, and userdata (which usually includes internal storage). Of course, that list is notably missing two common partitions: the radio/modem and the bootloader. Chainfire is still doing research on the radio, so it may be added in a future update. The bootloader has been left out intentionally because of the risks associated with a bad flash–it could brick a device–and possible complications stemming from atypical naming.
Userdata can be backed up, and it generally includes both /data (application data) and internal storage. When a backup is being made, FlashFire is smart enough to exclude other types of backup archives from TWRP, ClockworkMod, MultiROM, and its own backup files. This prevents redundant copies from making your archives larger.
There are a couple of important issues about restoring backups, particularly with regards to userdata. The first is that FlashFire doesn't technically restore fastboot-flashable backups. Users can run the "flash firmware package" command with the backup ZIP to get most of the partitions restored–but somewhat ironically, that won't flash the userdata partition due to technical limitations. The second major detail is that userdata backups restore from fastboot as unencrypted ext4 partitions. There are multiple implications to this, including reduced security and possible incompatibilities with some kernels, but it may be also be seen as an advantage by some users that don't care for encryption.
The last time we looked at FlashFire, it had gained the ability to install official OTAs from quite a few manufacturers, all while maintaining root. The latest update extends this feature with a new option to preserve the existing recovery partition after installing an OTA or ZIP. FlashFire will attempt to detect a custom recovery and enable this option by default.
Enabling Preserve Recovery won't actually prevent the recovery partition from being modified, but instead creates a backup of the current recovery and waits until the OTA or ZIP are finished installing before restoring it. If a stock recovery has to be present to complete an OTA, that step will occur transparently as part of the install, then the custom recovery is restored at the end of the procedure.
Get The Latest Version
If you have joined the FlashFire beta group in the past, just check the Play Store for an update (it may still take a couple hours to propagate). For those that aren't already part of the test group, the sign-up page is here. Keep in mind, fresh sign-ups can take a while to take effect on the Play Store. If you're in a rush to get the new version, Chainfire also has the apk available for download on his own server.