To get started, you will need the modified version of the game. This is a simple process, and you will only have to do this once to get access the Pokemon GO Free Spoofer but it's only for iOS!
When you spoof the GPS location on your iOS phone and then open Pokemon Go, the app thinks you're in the new location. That means it will generate Pokemon associated with that new area, and you'll also be able to take part in special events and gym battles based on the spoofed location.
Features of this Spoofer:
Encounter IV Checker
Nearby Gym Slots Scanner
Fast Catch Trick