THis is a great plan, and exactly what i did this year when i upgraded my iphone. Used the old one just for OnX. No updates or anything since it was working fine.I have an old iphone that I use OnX on. Works great, I'm a little scared to upgrade now! The phone has OnX only, I download maps at home on wifi, then it's on airplane mode when not at home. I'll use this setup until the phone is 100% dead and buried