You were doing some stuff and then suddenly your iPhone or iPad screen is stuck and the display is no longer responding to your taps. Apparently, your iPhone is frozen and therefore needs a restart. But since the iPhone screen is not responding to touches, performing the usual method won't be applicable. In this case, you will need to perform a force restart. As the name implies, it forces your apps to end and your iPhone system to shut down and then restart. This can help clear out minor software errors that caused the phone system to crash.
Familiarizing the iOS platform...