If you've been waiting for the iPhone's famous I Am T-Pain app to make it to Android you should try out MicDroid!
Always sing in tune!
Offers plenty of options for pitch correction!
Reproduce the pitch correction effects you hear in music yourself!

Features:
-Automatic pitch-correction
-On-the-fly pitch correction
-Email recordings
-Set recordings as ringtone
-Disable/enable ads in settings

Still BETA quality software so please report errors to the developer!

Source code available at http://www.github.com/intervigilium

Graphics courtesy of
http://pengxwang.com