suhail1786 wrote:
I think iOS 6 has the problem this was not the case in iOS 5 so according to me to turn wifi on even when your phone is in sleep is to let the safari browser running in the background yes it could use your battery a little but I think it is the only option available it worked for me
Actually, NO. iOS 1 had this FEATURE. iOS 2 had this feature. iOS 3 had this feature. iOS 4 had this feature. iOS 5 had this feature. iOS 6 had this feature. And its likely that iOS 7 will have this feature. You can confirm this by doing a search of the forum going back 7 years. You will see mention of it for every version since the beginning.
Its there because WiFi, when it is on, requires a continuous 30 mw of power, unlike cellular, which only uses power when sending or receiving. If WiFi stayed on all the time it would drain the battery in a few hours. Then you would see complaints about the battery draining fast, rather than WiFi turning off when the phone goes to sleep.
It is BY DESIGN this way. If you want to keep WiFi on when the phone is asleep just plug the phone into its power adapter. This overrides the automatic shutoff.