问题
Now, the Xcode 6.2 and SDK 8.2 are released. I want to develop the Watch App based on iOS App that the deployment target is 7.0, Must I set the deployment target to 8.2 if I want to develop my Watch App?
回答1:
The Base SDK must be 8.2. The Deployment Target can be anything you wish to support. But anyone using your app on a device with iOS 8.1 or earlier won't be able to use it with an Apple Watch. That requires a device running iOS 8.2.
If your app only makes sense when used with a watch, then setting your Deployment Target to 8.2 probably makes sense but it isn't required. If your app can do other things without a watch then it's fine to support iOS 8.1 or earlier as desired.
来源：https://stackoverflow.com/questions/29044941/is-the-deployment-target-must-be-8-2-when-i-develop-with-the-watchkit