Unlock Extra Boxer:
Enter your name as 'GETFAB' at the 'Create a Champ Mode' and save the profile. When you now go to 'Hard Hits' or 'Play now' Fabolous is unlocked as a Heavyweight Boxer.
Unlock All Venues:
Tap left 16 times in the 'Games Mode' screen until you hear a bell to unlock all venues. This cheat needs to be repeated everytime you restart the game.