I'm interested in hotspotting my iPhone 5 to my laptop through AT&T's service. If it was 100% battery, how long has your battery lasted for your iPhone 4/4S/5 if you hotspot all the way till 0%? I'm considering to pick up a battery pack case once they release for iPhone 5 (i.e. Morphie), and am also interested in knowing how much longer do these external battery pack cases keep your iPhone running when hotspotting as well. Thanks!