I have UISwitch on my vie, loaded from xib. It's x position is bigger then zero and it looks ok on iOS 5 simulator. But when I try to run it on 4.3 simulator it looks like UISwitch's position is equal to zero
Where is my problem?
As well as their change in appearance, UISwitches have shrunk between iOS 4 and 5. Based on quick screenshot comparison, they were about 94pt wide and are now only 76pt. So if you have a switch that is, say, right aligned per the autosizing mask then it will extend further to the left in 4 than in 5.
Sadly there's very little you can do about that other than designing for 94pt widgets and accepting a bit of extra empty space under 5. Because the interface builder positions all things at exact pixel positions, rather than applying a layout logic, it's quite possible you'll have to do some manual programmatic adjustment.