Tap the check in button on the bottom left corner of the app within the home screen. Scroll through the places nearby and tap the correct one. Not there? Try typing all or part of the name into the search box (looks like a magnifying glass) in the upper right corner.
Want to say more about your check in?
Type a 'shout' or mention a friend! To share a bit more information about what you’re up to, type out a 'shout' in the box provided or tap the camera icon to either take a photo or upload one from your gallery. To mention a friend in your 'shout,’ type the name of your Foursquare friend and tap their profile that appears at the bottom of the screen. This will hyperlink to their profile. Don’t feel like writing the extra step? No problem. You and your pal will appear at the venue together just by checking in.
Oops! I checked in to the wrong venue...
If you accidentally checked in to the wrong venue, deleting a check-in is easy. While in the app, tap on the drawer icon in the top left corner (it looks like three lines). Select ‘Profile & History’. Scroll past the color blocks of ‘friends’, ‘stats’ etc until you see 'History.’ From there, tap through to the check-in detail you wish to delete and tap the 'DELETE' button on the bottom right. Deleting check ins will remove any badges and points earned with that check in.