The Ghost Framework
Ghost Framework is an Android post-exploitation framework that
exploits the Android Debug Bridge to remotely access an Android
device. Ghost Framework gives you the power and convenience of
remote Android device administration. You can find different
versions of the framework on GitHub. E.g. ghost-1, Ghost and ghost. The tool allows e.g. running a shell, control the mouse and
keyboard and taking screenshots.
Plenty of vulnerable devices can be found with Shodan with the query:
adb debug bridge. Keep in mind that
some of them might be honeypots and not real devices.