Something that's just happened in the last couple of weeks. I've got an iPhone 4S and a time capsule. All my other devices (Mac Mini, iPhone 5, iPads, Wii, xbox) working fine with the Airport/Time Capsule. In the last two weeks my iPhone just can't keep a connection with it. It'll connect to the Airport but it won't be connected to the internet. I updated to the latest iOS 8.1.2. and it worked for a while then stopped. I've used other wifi sources out and about including my local Apple store and the wifi works fine. It just seems to be my phone and my Airport that has an issue with each other. I've tried resetting network settings but doesn't make a difference. Any suggestions gratefully received.