My wife has inherited an iPhone 4 from our grandaughter(don't ask why).
The phone connects easily to my BT Home Hub 3 wirelessly at full strength in the room where the hub is. If she takes the phone out of the room it loses the connection. Other family members with iPhones have no bother anywhere around the house.
Has anyone any idea what may be causing the problem?
I sat by the router and had a five dot connection indicated to the Home Hub. Took the iPhone into the back room and dropped to between a 2 & 3 dot connection but was still able to use the phone to access the internet. However, when selecting "settings" the home hub was not visible and it said wireless disconnected. I assume it was then actually connected to the nearest external signal rather than the home hub. Not to worry the wife will never use it to access the internet anyway.
Can't think of any other reason. There has been some iPhone 4 problems after updating iOS 7. Some people are saying DON'T upgrade your iPhone 4. I upgraded a relative's 4 a couple of months ago, though, and no problems whatsoever. Very strange.
Thanks for the advice both of you but nothing has made any difference. There's probably a hardware problem with the handset. As I said, the wife won't use it to its full ability anyway.