I have recently moved from France to the USA. In the long run, that means I will shut down my French bank account who is becoming useless. But I cannot go on iTunes and change the "bank account" settings or change my address there.
From this article, I believe I will have to buy again all the apps, movies and music I have previously purchased, as well as "forget about" French apps not present in the U.S. store, even the ones for which I wish to keep an account active (not sure how to do that). I believe one cannot "switch" between a US and a French iTunes account at will. I will probably also lose all my Game Center scores, etc.
1 - How can I measure how much data / apps / settings will be lost?
Also, iCloud documents.
I have several hundred iCloud documents stored in Textedit, Notes, Pages, etcetera, that I absolutely need to work on, on a day-to-day basis.
2 - If there is a simple, step-by-step procedure that would allow me to migrate to a US-based iTunes account with as little loss as possible?
3 - What happens if I move back to France in 5 years? Same losses?
Models of devices: iPhone 4, iOS8, and iMac mid-2011 with Yosemite.
I understand that 1, 2 and 3 are different questions, and if anyone has a problem with this, I will gladly split the question in three different question pages, just let me know.