how to set minimum os required in iphone

I have to check whether my app is compatible with iOS 4.0 or not.

I have tried looking out for certain forums but 开发者_Go百科all I can see is to change the iOS deployment target. I have done doing so also but still my app is running fine. I have changed my deployment target to 3.0 but still it works fine. Since I have used Gesture recognition which was introduced later. It must crash my app (but still it is working fine).

So I want to know Is there any other way out to check my compatability.

Or is it the problem because I am running it on Simulator rather than on device(my device has iOS version 4.2).

Any comments or answers are really appreciated.

Yes thats the reason that your app is not crashing because you are running it over simulator which has the ios version 4.2.Because now your ios version is updated on the simulator so you are able to test the Gesture Recognition over that.You are correct .

If you have an iPhone that is certified for distribution you can just run it on your device and test your firmware versions from there. Hope that helps...