Hot answers tagged backup
A very easy way is ES File Explorer from Google Play Store. You can browse to your /system/app folder (for system apps) /data/app folder (for user apps; requires root to be accessed) and copy them to your /sdcard (or anywhere else). Copying multiple files with ES File Explorer is very easy. Just long hold one of the files, then put check marks on all ...
No, download mode doesn't provide you with access to the phone's files, and yes, the error message you see looks very much like it's telling you you're trying to boot an unsigned ROM from a locked bootloader.
There are several apps specialized on this topic. The probably best known is AppMonster, which I use (in the Pro version) for years now, very reliable (and very active dev). For alternatives and more details, please take a look at: Are APK files saved on my device when I install from the Play Store? IzzyOnDroid App Lists: Backups: Backup Apps
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