I’ve been using Touch ID since I got an iPhone 5s in mid-October. Generally speaking, I like it, and I find it faster than the old swipe-and-passcode method, but I’ve felt compelled to reteach it my fingerprints twice already. I know this sounds impossible, but its recognition of my prints seems to decay with time.
I rescanned my fingers this weekend, and Touch ID has been amazingly fast and accurate since then. Just as it was when I first got the 5s, and just as it was a few weeks later when I rescanned my fingers for the first time. Just before each rescan, though, I was so frustrated with Touch ID I felt like throwing the phone across the room.
Curious observations by Dr. Drang. I don’t think I’ve encountered this problem myself, though I have also dedicated three of my five Touch ID slots to a single thumb to increase accuracy and speed. If this happens, and happens on purpose, I would have to wonder why Apple would do such a thing.