SlotZ Racer it's a must for racing fans, in my opinion. It's a great slotcar racing game with loads of features. It's not free, $1.19AU from the App store, which is very cheap compared to other apps I've downloaded.
It has two single player modes, Quick Race and Single Player. Quick Race puts you in a random car and track for a set amount of laps. Single Player is a bit more complex, it features Single Race, where you can set up a race with any car, circuit and other options. There's also a practice mode, where you go out on the track by yourself and as the name suggests, practice. Then there's Championship where you can go through a whole "career", starting with championships consisting of 3 lap races and working your way up through endurances and Grand Prix-like championships. You are also able to create your own championship, which works pretty much the same as Single Race, but you're setting up a whole championship. Winning championships unlocks more cars and circuits to use in the other modes.
There's also my favourite feature, the track editor. You can design pretty much any layout you want, with elevation, corners of almost any kind, banking, "lane switcher", chicanes and some rather bland scenery. Then you can go off and race the AI on your circuit.
Another game I found pretty entertaining was Audi A4 Driving Challenge which was produced by Audi themselves. It's more of a time-trial racing game where you work your way through a limited amount of courses beating the set times in the Audi A4 2.0T. You are able to unlock two more cars, the A4 3.2 and R8 by beating the record times. Unlike SlotZ Racer, this game makes use of the Accelerometer which takes a little getting used to but once you do, you should be fairly comfortable despite looking a little stupid in public.
Audi A4 Driving Challenge is a free download. I don't find it as entertaining as SlotZ Racer, but it's still quite enjoyable and worth it if you're an Audi/automotive fan.
