I have created an app, and then later changed the core data model. I changed the model and this all works fine during development. However to my surprise, when users download the updated version (with the new core data model), the app keeps the old model from the previous version. This causes the app to crash.
Is there some way to simulate an update as if it was updated from the app store? I need to be able to do this in order to test my possible solutions to the problem.
You cannot simulate update in XCode, look at this: https://developer.apple.com/library/ios/technotes/tn2285/_index.html
You have to create IPA file and process update via iTunes over older version downloaded from AppStore.
Build and install your old version, generate some data, and then install the new version on top of it.
For testing before submitting to the Appstore I generally download from the AppStore again the old version, and then install with Xcode the newer version - for your next update... ;-)
来源：https://stackoverflow.com/questions/3268079/simulating-an-update-in-iphone-sdk