GPS is only a tool to help with one question.
Not really - these days GPS effectively answers a host of questions;
How far is it to the alternate,
What other airfields are within range and how do I get to them,
What is the next and the next frequency,
What does the plate for the airfield look like,
Where is the traffic that just called,
What is the weather doing ahead,
What is the wind doing,
What is the outside temperature,
What is my ground speed and airspeed,
What do I need to do regarding controlled airspace,
Where are the danger areas.
I could go on. It is all there for you on current glass displays, if not exactly a simple GPS.
I cant do half of that in real time in my brain so I am glad to have the technology on my side.