Replace resource png's directly on iPhone (iPad)

I have some png's that are now resources in XCode.

I would like to replace the with other png's on the device after deployment. How do I do that, while still being able to work with them in XCode?

I thing it should be "Documents" "Library" or "Settings" folder, but it is not so clear how to create them in xCode.

(This is an internal app, no appstore, no clients, the files shou开发者_开发问答ld normally be manipulated from a connected computer).

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You can't modify resources in your app bundle without a jailbroken device.