Part of what makes Snapchat so addicting the assortment of eccentric lenses, filters, and stickers you can use to customize your snaps. The lenses option, which Snapchat announced last September, can transform your face into that of a horrifying monster or make it look like you're vomiting rainbows. Lenses are a bit similar to apps like Zombiebooth and Face Swap, which apply special effects over an image to distort your appearance.
Snapchat, unlike most social networks, isn't the easiest app to get started with. Many of the app's features aren't immediately obvious unless you've spent some time fiddling around with it. This is especially true of Snapchat's lenses, which aren't even visible until you press and hold on a person's face when capturing a photo or video. When applying a lens, Snapchat may also ask you to make a silly facial gesture, like opening your mouth or raising your eyebrows, so that the lens fits properly. If you don't like any of Snapchat's lenses, you can draw your own by choosing the doodle option from the list.
Check out the video above to see how to use Lenses.