re: Apple iOS Fingerprint Scanner Has Security Limits
This is a tough one to call. The sensor seems more sophisticated that what I've been seeing previously, even including Authentec's earlier versions for other companies.
The point with this is not just speed, but not needing to remember the number, which might seem easy, as it's only four numbers. But people do sometimes forget, or, as you pointed out, hit the wrong key, sometimes, several times in a row, particularly when in a hurry.
This should be more secure than a four digit pin. And, it's more for the casual thief, who won't want to bother figuring out a way around it. Removing a fingerprint from the phone may not work well anyway.
I would just prefer they used a forefinger instead, as that's how we tap our phones normally, but perhaps we'll get the choice as to which finger to use. I don't know how it could tell anyway.