[jchimney]

Its an improvement. The typical pass has 4 characters so 10,000 possible combinations. Doing about 1 per second would find the password in the worst case scenario in about 3 hours; simply by trying all possible combinations.

I think trying to lift a usable fingerprint off a glass surface would be significantly more difficult than that.

[coldcode]

No, each failure increases the time between tries until you brick the phone.