Pinterest (Free)

Whenever you see stuff you like on the Internet, Pinterest gives you a way to share it. You can post items like photos and videos on your various Pinterest “boards” just like you would on a bulletin board — except online, where others can like your posts, share them, comment on them and follow you to see what other posts you’ve made.

Foursquare (Free)

For a more real-world, location-based social experience, Foursquare is king. It encourages users to “check in” at various places, from landmarks to local restaurants, in order to share what they’re doing and their favorite places. You can use Foursquare to meet up with friends, and check ins can also be good for discounts at some businesses.

Facebook (Free)

If you want to be tied into social networking on your mobile device, there’s really no substitute for the original Facebook. The app outdoes it’s smaller counterparts simply by including just about all the features you can get on the web version of the social network, like the ability share updates, message friends and view their profiles, and more.

Vine (Free)

Vine is for video what Twitter is for text. The app is built around users sharing short videos with friends and followers — each of the videos is only six seconds long, so the idea is to capture everything you want to show as quickly as possible. You can share your own videos or check out those of people you follow, and Vine makes it easy to find other great videos made by others as well.

Path (Free)

Facebook is great for connecting with people, but users tend to accumulate huge numbers of “friends” who aren’t really friends. When you add everyone you’ve ever met on Facebook, it’s possible to find yourself seeing posts you aren’t interested in, or worrying about sharing more private information with others. Path eliminates that issue by creating a smaller social network of just 50 of your closest friends or family. You can still post images, links, videos and more, and comment and like them, but with the knowledge that your posts are seen only by a select few.

SnapChat (Free)

Part messaging app, part social network, SnapChat encourages users to communicate with pictures and videos more than text. It works by allowing you to send messages by snapping a photo or shooting some footage, then adding a text caption and sending your post along. The messages you send only last for 24 hours, and encourage you to do more than just bash out a text message.

Instagram (Free)

Mobile photography fans, Instagram is the social network for you. You can use it to snap photos and add filters to enhance them and give them a vintage look, then share them online with other users. But Instagram is also a huge social network of other users, who you can follow and interact with by seeing their photos, leaving comments, liking what they share, and more.