I am currently developing a racing game for ios. I was wondering, what should be the max polygon count for the car and the track.
I am targeting the iPhone 4 as the minimum device.
Here we go again. It’s impossible to give you a hard and fast number. The value that works for you will depend on a million factors, including the framerate you want, the complexity of the shaders you use, whether you use any alpha effects, the depth complexity of the scene, whether your performance is limited by the CPU, GPU, or the bandwidth between the two.
As an illustration, consider the question “I am about to buy a car. What mpg will I get?” That question also cannot be answered for the same reasons. It depends on the kind of car, how well maintained the engine is, what tyres are used, what fuel is fed in, how the driver drives and a million other issues.
Nothing like a good car analogy.
How about limiting yourself to mobile diffuse shaders and then I’ve read from independent sources and experienced you can get ~30 FPS with 150K - 200K on iPod touch 4th gen iOS 6.1. You can still get a rather pretty viewport with mobile diffuse only shaders if the art is suitable. So if you have 10 cars in scene at once (very crowded scene so doubtful) allocate 10K per car and that leaves you 50k - 100k for the rest.
Here is a good baseline in poly count (LODs) for cars used in mobile game development. Scroll down and check out the LOD poly counts and wireframes.