Jacob Shamsian/INSIDER
Snapchat's coolest filters are geofilters. They're crowdsourced and paid filters that can only be used by people in certain areas. Snapchat uses your phone's GPS location services to find out where you are, and then gives you the filters for that place.
There are two ways to get geofilters: The first way is to actually go to a specific place. The second is to fool your phone into thinking you're already there.
That second approach is called GPS spoofing. There are several apps that do this. I like Fake GPS for my Android phone. For iPhones, you need to jailbreak your phone and find LocationFaker in Cydia, an alternative to Apple's app store.
All of these apps basically work the same way. Here's how I traveled the world with Fake GPS: