When I was developing on Snow Leopard (Mac OS X 10.6), Xcode had a nice list of previous iOS versions and iPhone/iPad generations for compatibility testing.
Now that I “upgraded” to Lion (because Xcode 4.3/iOS SDK 5.1 required it), all those Simulator versions suddenly disappeared, leaving me with only iOS 5.1 to test with. Xcode 4.2 wouldn’t run on Lion, even though it doesn’t want to be uninstalled, either.
So, the question is, how do I test my apps on the older versions of firmwares and hardwares on Lion OS without physically owning all those devices? Can I somehow get the Simulators came with Xcode 4.2 to run on Lion?
Go to xCode on the place you choose the simulator press on it and click on more simulators
you will got the below screen through you can install any old versions of simulators.
Good Luck.