Sensitive display, Prevent pocket dials
This 2 features are nearly based on hardware used.
In sensitive screen,
In cold regions or peoples who wear glove will get benifit of this feature.
It will make screen more sensitive and you can touch by wearing gloves also.
Prevent pocket dials,
This is common problem.
So many times phone unlock and do something in pocket.
So when we toggle this feature it will detect that phone is in pocket and it wont allow phone to do anything till phone dont come outside of pocket.
It can be tested by keeping hand on the top of screen, in front of sensors or camera. And try to unlock it. It will dont allow you to unlock.