How to brick Samsung phones

Just rebooting the phone won't clear it up, however, it would be a little more complicated than that. The use case this dev is presenting is that they have somehow gotten a user to install this malicious app and approved it for the permissions it requires.

Once it locks the device you don't even need to wait for the battery to die, you can simply hold down the power button and it will power off after a few seconds.

The issue is that the app sets to auto run on boot which means you would have a small window to uninstall the application before it locks the device again.

So if you were lucky enough to have enabled USB debugging prior to installing this app you could run an adb command to uninstall it. If you're technically savvy enough you could load a custom recovery and delete the malicious app from there.

..or, simply, you could just factory reset the device and the malicious app would be erased as part of the profile reset.