I currently have two grandfathered UNLIMITED data plans for my two phones (two separate lines). Data usage currently rarely exceeds one GB (averaging about 1/3 GB).
I've been wondering whether I could transfer one of my grandfathered unlimited data plans to a 4G tablet that would use much more data, both Wi-Fi and 4G. I'd then get the lowest tier data plan for the second phone line when I upgrade my wife's phone.
I know that predominently Wi-Fi usage and temporary tethering while away from hotspots would probably be the least expensive way to go, but if one of my unlimited data plans could be used, it would be an option.
Actually you can. You just have to get a 4G phone on that line first to get it to 4G data. It'll stay unlimited if you activate a 4G phone. Then just take the SIM card out of the phone and put it in a tablet and you're good to go. You still have unlimited data and the plan is still the same as on the phone. $9.99 for the line and $29.99 for the data, if that's what it is. With 4G you can move a SIM from one device to another and it'll work fine.