ADB Toggle is a security tool that allows you to toggle the USB debug settings. You can toggle with the homescreen widget or use the automatic mode. In the automatic mode the USB debug settings will be disabled when you unplug your phone (or turn off your screen), and is only enabled again after you have unlocked your screen. Additionally there's also a reboot feature that lets you boot your phone into recovery or bootloader mode, or perform normal/fast reboots.
Please be aware that the automatic mode is not available in the free version! You have to buy the license key to unlock this feature!
ADB Toggle will only work on a rooted phone! Once the app has installed itself as system application then root access is no longer needed.