I have characters and worlds saved locally on my device and I'm wondering if it is possible to change them so that instead of being locally saved, they're saved to the cloud (iOS), if so how would I go about doing that? Many thanks for any help!
Last I checked (Dec 2015), you explicitly can't.
Someone had gotten a new phone for Christmas and lost their saves. On thinking it was a simple file transfer (didn't know iOS) and researching it to help them, it turns out local saves cannot be transferred to cloud saves once they are created. There is no option to move a save file inside the game, in any manner, let alone between cloud and local. Local saves cannot be accessed for a straight device copy either, unless the phone has been jailbroken to allow it.