How to restart android, without touch or removing battery? All of a sudden my Android (Lollipop) stopped responding while I was using an app. I pressed the power button two times and the problem persisted.

I waited a few minutes and pressed the power button again. It showed the lock screen, but still the smartphone (Moto G) didn't respond to my touch commands.

How can I reboot my device? I can't touch the "Power Off" option neither can I remove the battery.
Press and hold the power button for 10-20 secs and your phone will force reboot, in most cases anyway. If your phone still doesn't reboot, then you'll have to remove the battery and if its not removable  you'll have to wait for the battery to run empty.