I'd like t' point out that this be the iPhone version because I be too goddamned impatient t' wait for any better release. Besides, I be not focusing too much on the controls anyway.
First a all, let's start with Sonic 4's wonderful innovations.

This be Casino Street Zone. Obviously the most unique level in the game. Not modeled after any other level, no siree this be 100% original bullshit we have here.
The music be nothing short a amazing. Listen t' this shit:
http://www.youtube.com/watch?v=Eo_ENChT5FI
Golden. Greatest ingame music t' ever exist.
Design? Only the best t' ever exist. Sure ye hold right alot 'n the game pretty much directs yer movement at all times sailing away ye hardly any freewill but it looks so damn cool while it does it. it be like "Shit we know ye're bored but look at all this shiny shit isn't this game awesome" 'n obviously it be if ye haven't caught on by now.
Buy this shit because even though it be ugly 'n a ripoff a Sonic 2 'n the music sucks 'n the design be practically nonexistant it be Sonic 4 *crag*ers therefore it be worth it.