All phones I’ve used in the last years turn on when you tap the touchscreen once or twice while it’s off.
(Hopefully)Most phones are locked when they are woken up.
Call the target, screen turns on, ghosttouch to answer before it even rings
Why would screen turn on in your pocket? Smartphones have light/proximity sensors to turn off the (touch)screen when you put it near your head so that you don't tap things with your ear. It should not turn on. If it does, it's programmed badly.