U.GG 
Icy Veins 
Arcade Cloud 
EV.IO 
Luminosity Netbot, The Tweetbot for App.net Goes Free
Netbot and Netbot for iPad have gone free. While App.net has failed to take over the world, yet, if you are interested in this alternative to Twitter, you'll be hard pressed to find a better client to use with it.
Jeff Scott
Jeff Scott is the founder of 148Apps and an app obsessed writer who loves talking apps, games, and the business around them. He knows what real football is, but still insists on calling it soccer.