With your GPS you can decide to block certain numbers depending on the location where you are. You can block your boss phone calls when you are at home. When you leave home with your phone the boss will be able to call you when you are 250 meters away.
You can either:
-Block certain phone calls in a localized area.
-Block all phone calls in a geographical area.
-Block certain calls everywhere.
(I.e.) Block Paul when I am at Maria's place. Block all calls except Mary's when I am at the office. Block all Ron's calls everywhere. Block all calls when I am at the dentist.
But you must be sure that your phone knows where you are! Don't forget to start your GPS up.
Select some areas in the geolocalizer and store them in the application.
Create rule linking a phone number to an area.
Choose the type of blocking you want to make