It's not an iPhone but at http://forums.cnet.com/7723-13973_102-560420/wifi-disconnects-from-time-to-time-galaxy-tab-7-plus/ covers a common issue. Also some folk are just too far from the hot spot. My son's iPhones are fine and I continue to run into the channel and distance issue.
I have a iphone 5s and the data usage is huge I feel like things are running but I don't know how to turn them off? and it has trouble picking up and or keeping a wifi signal what can I do? any suggestions would be helpful thanks