How To Access the Developer Options Menu and Enable USB Debugging on Android 4.2
 

In Android 4.2, the Developer Options menu and USB Debugging option have been hidden. If you need to enable USB Debugging, you can access the Developer Options menu with a quick trick.

The developer options aren’t just used by developers. USB Debugging is required by adb, which is used for rooting an Android device, backing it up, installing a custom ROM, taking screenshots from a computer, or doing many other things.

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