I’m about to switch my outdated Samsung tablet and smartphones to LineageOS. But I want to make a backup of my device, including the OS and everything, in case something goes wrong and I need to flash the original OS back into the device.
How do I proceed? I think I need to do a Nandroid backup or something? Is that correct?
Generally not possible either. Unlocking the bootloader always wipes the phone. So unless it’s already unlocked, or it can be unlocked with some sort of exploit instead of using fastboot, it’ll be worse than a (bad) normal backup.