Sonic The Hedgehog 2 Classic, like the 1st game available on Moblie is the definitive version of the game. But includes more than the previous port, being the additional of a new level, the scrapped Hidden Palace Zone. This is a great way too make the game have more replay value. Again, it has the original 3 available too play with save states and achievements, but now you with more levels and more reasons too play, Sonic 2 Classic is the best out of the two.