I've had a stable battery for a few weeks now after the last time I posted about this issue. The problem I originally had was that I was losing 10-15% on flight mode overnight with only the cnn, bbc news and the battery apps allowed to run in the background.
Somebody quite rightly posted that the two news apps would try and pull through new data every hour. I sorted them out and all good.
Last night my battery went from 44% to 4% on flight mode! The only thing I can think is that I had just been on whatsapp before switching it to flight mode and can't be 100% that I had closed the app
The only slight (and I do mean slight) quibble I have is with the battery, compared to the 4S I had it does eat it faster. Don't get me wrong I really love the phone and don't miss IOS at all. Yes I also know that it isn't the phones fault if I have poorly written apps on it.