I have had the iPhone 4s since the day of launch and had a problem with it every day. Basically it keep killing my home wifi/broadband. I will be using it as normal on my home wifi then all of a sudden I notice the wifi connection has dropped and the small circle is in it's place. When I go to my router that is still showing as connected - my computer however has lost it internet connection too. The iPhone then just reads 'Unable to join the network "BTHomeHub2-......" Other relevant facts: -I'm in the UK using BT broadband 14.7Mb Download speed & 0.9Mb Upload speed -I had a iPhone 3GS for 18 months with the same set up and had no wifi issues.