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Does ADB Back Up contain system files? Supposing an un-rooted android device has got an ADB back up and something goes wrong and the device does not boot up, then can the ADB back up be useful?

marked as duplicate by beeshyams, Dan Hulme Aug 10 '16 at 18:02

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  • Related / duplicate of android.stackexchange.com/q/28296/131553 – beeshyams Aug 7 '16 at 8:54
  • The usefulness in your described case is you could factory-reset the device and restore the backup to get most things back. For "why not all things", see the linked question (apps can opt-out of this backup, and some data like SMS is not contained). – Izzy Aug 7 '16 at 10:31

For what ADB backup does, you might wish to see our tag-wiki. Basically, depending on the command line switches used, it backs up apps (.apk) and their data.

As for the second part of your question, you might wish to see Is there a way to look inside and modify an adb backup created file? Yes, it's possible extracting parts of it, and yes, Titanium Backup is one of the apps capable of this. Other ways are described in the linked question.

Also worth a look:

Answer taken from What all does ADB backup and how do I restore part of it?

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