If I install iOS 4.1 on my development phone, will I be forced to upgrade the SDK?

I want to开发者_如何学Go install iOS 4.1 on the phone, but I don't want the hassle of installing a new SDK version on my computer especially with XCode 4 on the horizon. Will I still be able to debug using the 4.0.2 SDK with iOS 4.1 on the device?

You can not debug if your SDK is lower than the OS. But you can build an adhoc build for lower version (say for 3.2 or 4.0) and then sync that with your iTunes (provided that you can access your iPhone 4.1 with iTunes). But NO debug build if SDK < OS.

You'll need to upgrade. When you fire it up, it'll say it can't find the correct version in the xcode organizer. The opposite will work fine (Upgrade SDK and use earlier version of device).

It's a big download but I'd just suck it up and do it. The XCode 4 version is the only thing on the horizon for a little while it seems.

Unfortunately, you need to upgrade the SDK if you would like to test your applications on 4.1 device. Using 4.1 device with 4.0.2 SDK will not work (the Organizer will ask for a compliant device).