
Menu Screens
The menu screens on 'Sonic 4' are beautiful, they are really simple to use, and you can't get lost in them. The UI reminds me very much of the Nintendo Wii, with the large buttons, however I think they were a good choice for the iPhone.

After completing the first level which you will get thrown into after pressing 'New Game', You unlock all of the levels available on the game. This is different to the previous games, as they used to play in sequence. The only levels 'locked' are the boss levels, and special stages
Levels.
There are 4 'zones' in this game, not including the special stages. Each of the 4 zones, have 3 Acts, and 1 boss level. There are also 8 special stages.
Unlike the older games, the boss levels are playable separately to the final act.
The levels are similar to those of the older games, however there are also new features, including new boss moves and boosters (lots of them).

The Special Stages, use the iPhone's accelerometer or the touch screen to play (this is selectable in the menus)
Also there are 2 iOS exclusive levels, '100,000 Points (Casino Street Zone, Act 2)' and 'Strange Mine Cart, (Lost Labyrinth Zone, Act 2) ' that are different to the normal gameplay.

Strange Mine Cart, has Sonic in a Mine Cart, using the accelerometer to go along a track. You tap the screen to jump, and you simply guide the Cart to end of the level, avoiding enemies and obstructions. This level is exclusive to iOS too.
Graphics
The Graphics for an iOS game, are superb. One of the best graphically intense games, I have seen on the iPhone. If you compare the graphics to Sonic 2 (I know its unfair), you can see its a true 2.5D game.

Controls
The iPhone version of the game, offers 2 different control sets.
Touch Controls, and Tilt Controls.
The Touch Controls, offer a virtual joy pad and one button to jump, spin, attack. When you are using the Touch Controls you have a choice to use touch or tilt in the special levels.

Your other option is Tilt control, this uses the iPhone's Accelerometer to run, and you tap the screen anywhere to jump. To perform a spin dash, you have to tap on Sonic himself.

Gameplay
The Overall Gameplay is fantastic, Its fast and goes right back to the original 2D Sonic Games. There are a few moments where the game plays itself, with strategically placed "boosts" and springs, but overall the original game play is there.
The Homage Attack is alot of fun to play with as it locks on to your enemies allowing you to perform quick Combos, this is great for points and game flow.
Homage to the Previous Games
There are a few subtle homages to the older games.
Sound: All the sound effects (rings, spin dash) are exactly the same as the original Sonic.
Sonic: Despite the fact that the Sonic you play as is designed off the new modern design of Sonic, the original sonic makes a cameo appearance in the loading screens of Sonic 4.

These have changed the font and some colours, but they are exactly the same as the 1991 counterpart.

Rating

Requirements
OS: iOS 3.0
Device: iPhone, iPod Touch, iPad
Size: 88.7MB
UK Price: ?5.99
US Price: $9.99
CA Price: $9.99
[[URL="http://itunes.apple.com/gb/app/sonic-the-hedgehog-4-episode-i/id392788790?mt=8&at=10l3Vy]iTunes[/URL]]