Doesn't it also depend if you are using a 3G or 4G phone? I have a Galaxy S3 with unlimited data and activate my Hotspot when we travel to visit my parents (for the kids to use their ipads, 5 hr drive) and turn it off when we get back, so about 4 days. It's about $1 a day or less with my corporate discount. I get unlimited hotspot with my 4G data plan, but sometimes I switch to my iphone 4s (only uses 3G) and when I try to activate my hotspot, it only gives me 2GB data for $30 (even though I have unlimited 3G also). I actually haven't activated my hotspot on the iphone because of this. Is this an iphone thing or 3G thing?