Hi, there isn't much choice on iOS, since we don't have access to local FS comparing to other platforms, so the above media backup is probably your best/only bet.
It will upload your selected media one by one to Automatic uploads
location (you can change it in the settings).
What "pay to use" option you have in mind? Background functions are in fact limited to Ultimate version, however honestly speaking you might not need them anyway if you start app from time to time.
I hope this helps, please let me know if you've managed to backup your media succesfully. Thanks.
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