Geofilters let you add specific, location-based filters to your photos. For example, if you snap a picture in Manhattan, you'll see different geofilters compared to if you were in Brooklyn. Some think Snapchat may eventually monetize geofilters by stuffing ads into them when you send snaps from certain locations.
To see which geofilters your current location unlocks, all you have to do is swipe right on the preview screen before you send a snap.
Here are a few examples.
Geofilters require you to turn on location services to allow Snapchat to sense where you are, but Snapchat doesn't store the location data.To enable geofilters, you'll need to first head over to your phone settings. For iPhone users, go to Settings > Privacy > Location Services. Toggle Location Services on and then scroll down and make sure the individual Snapchat app is toggled "On" too.
Next, open Snapchat and tap the settings cog in the top right corner.
After choosing the "Manage" option, you can now toggle on Filters, which will enable geofilters.
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You can now discover new geofilters just by walking around to new places, just remember to swipe right to cycle through the options.