Developing an iOS 3.1 app with SDK and iOS 4.0 device?

Question

I developed an iPhone app for iOS for deployment 3.2.

But my client changed his mind and wanted the application to be available for iOS 3.1. Thus, I installed iOS Deployment Target 3.1 and left the base SDK up to 4.0, but everything compiles fine, while I'm sure that I only use methods and classes that are only available in iOS 3.2.

How can I identify code that will not work on device 3.1? (and may cause the application to crash)

My problem is that I have one iPhone device (with 4.0.2 installed) and that the SDK 3.1.x is no longer provided by Xcode.

Answer 1

, : xcode sdk . SDK : http://iphonesdkdev.blogspot.com/2010/04/old-versions-of-iphone-sdk.html

, , .

Answer 2

? , , , - . , , >= 3,2 . , ?

Answer 3

, 3.1, - 3.1. (pre-iPhone 3G S) . , . , , Info.plist , .

, , , . , , , API.

iPod touch eBay , ​​ 4.0. , - . , , , .

Sorry, but this is the only way to make sure. Another developer told me: "If you have not tested it on a specific version of the OS or device, consider how your application does not start there."