One of the apps I have installed is not working super well and I'd like to try deleting its data to see if that helps.
Usually, when you delete an app on iOS, it warns you that all data will be deleted. As such, the common advice is simply deleting the app and then redownloading it from the App Store.
However, this app has been delisted from the App Store, meaning it can't be redownloaded, so I don't want to delete it. What else can I do?
For what it's worth, this is an iPhone 4 running iOS 7.