I have an iPhone 4 that sometimes will loose wifi connection. Cellular data is turned off and all data is restricted to wifi only. Will work for a while and then load slowly or not at all. Have to manually turn off wifi and then turn back on to get it to work again. After a while this process keeps happening. All other devices in the home including PS3, Wii, and my other iPhone 3GS do not have any issues. Only the IPhone 4 has this disconnecting issues or totally does not detect the wifi at all sometimes. Please help!
Is this on all WiFi networks, or only your home network? If it's the home network try rebooting your router by turning it off for a few seconds. In either case go to Settings/General/Reset - Reset network settings. You will not lose any data, but will have to re-enter your WiFi encryption passcodes.