XCode and recent iOS SDK

I am currently using XCode 3.2.2 and iOS SDK 3.2. With 开发者_StackOverflow社区these I can produce binary which works on iPhone 3.1.3. If I upgrade to XCode 3.2.4 and iOS 4.1, would I still be able to build binaries for iPhone 3.1.3 device? If no, can I install both, or it's tricky?

Eiko is correct, what's more I believe that apple will no longer accept applications built with pre 4.x SDK.

To get this set up you need to change the following settings

• Set the "Base SDK" in your projects settings to the newest version number of iOS whose features you may want.

• Set the "iPhone OS Deployment Target" to the oldest version number of iOS that you will support.

Courtesy of CocoaWithLove

Regarding installing multiple versions, it's not tricky... just awkward. The release versions of XCode are installed into the /Developer directory. To install multiple versions you need to move the /Developer directory to something else e.g. /OldXCode and then install the new version (Which is put into /Developer)

Hope that helps

You can, and you should, always use the latest SDK.

You can easily build agains 4.1 and still target 3.x - in fact most developers do this at the moment.