I have noticed that the new 3GS has a different gamma setting to the 3G. Naturally this poses problems in development.
I have a game running great on the 3GS that comes out a little too dark on the 3G and ruins the art style a bit. I tried turning on fog, but the results aren’t as great as I hoped.
i think the problem is worse and just detecting the device won’t help at all. I have word from one of my beta testers that on his 3GS the gamma setting is much darker than on my 3GS - and in the thread above someone mentioned his first gen. touch is brighter than his iphone.
This picture from macworld shows the difference of dark pictures between a good and bad display pretty good (on this picture you see a first generation iPhone and iPod touch):
Maybe in my situation it might help to use a skybox without PVRTC compression for the night scenes - at the moment it really looks f*** up on the touch with lot’s of ugly pixelated grey areas on the sky.
Also the fade to black of the unity splash screen looks pixelated on my touch.