Of course, part of the huge boom in smartphones is the ability to connect with others, especially through the rise of social media. Networking sites like Facebook, Twitter, and even LinkedIn are now standards to have when out and about. For you social network addicts, you'll be happy to know that your Android comes with both Facebook and Twitter, but what if you want something a little different?
Best in Social
Google Plus (Google+) - I admit it. I'm addicted to the new social network on the block, Google+. As a friend of mine put it, if

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Facebook and Twitter had a baby, it would be G+. Engaging conversation, no 140 character limit, and you can put people in circles to avoid awkward photos being shown to your boss or mom. The updated version now includes the ability to share conversations on your phone.
HootSuite - If you're like me, you've got Facebook and Twitter, but it's such a hassle trying to keep up with both (especially if you've been sucked in with G+). HootSuite lets you check both from one application. Send and receive tweets and check the feeds on both sites. I'm still waiting for the mobile's LinkedIn integration.