Ever since 9.1ish (can't remember exact time it started) TouchID has been crap on my 6 plus. It always worked great before. Now, it works maybe 10% of the time - a huge difference. I'm making sure it has been kept clean. Phone has been factory reset during that time. Is this a documented issue? I think it's software related, as right after the 9.2 update, it began working perfectly again for a few hours, then went back to sucking the next day.