If you have a 5s, and if your TouchID works immediately after you set it, but then stops working, I suggest you try the training method. Link. To "train" the TouchID, you give it lots of scans. You do this by first saving a thumbprint. Then you go back into settings, then the TouchID submenu, and then simply place your thumb on the home button while in the TouchID menu (but don't select any particular print). Each time you do this, the 5s scans your print, and you know it both scanned and registered the print because you are given a very quick indication via a greying of the fingerprint number that was recognized. You can do this over, and over, and over. What I did is I set up two fingerprint thumbscans. One for the thumb tip, the other for the flat part of the thumb. After these two prints were saved, I went back in and did the training, or "overtraining" as some call it. I did it maybe 50 times. Next day, another 50 times. It would toggle between prints one and two, and I purposefully moved my thumb from flat portion to tip. Previously, I had severe TouchID "fade." It wouldn't work after a day or two. A week, forget it, never worked. After the training -- flawless operation so far. 100% effective. This is like the best thing ever for TouchID. This should be a permanent IOS feature. Note to Tim Cook, Ivey, and Apple: please leave IN this TouchID training feature. It is essential for those of us who want an absolutely flawless TouchID and are willing to spend ten minutes over a few days to really lock in a couple of solid print scans. Direct every IOS team member that this TouchID training will forever be a part of the iPhone/IOS ecosystem.