Really killer for things like providing access to Airbnb guests without having to be there.
Kwikset also sells an iphone enabled lock, but an extremely cursory search didn't turn up a patent for them.
I wish them the best, but I'm having trouble coming up with a compelling argument to buy from them instead of buying what appear to be more mature, fully-featured products, backed by major lock manufacturers that are pretty well guaranteed not to go away in a year or two.
Current users who encounter this usually find some way to unlock their door for their guests after a phone call, leaving keys inside. The prevalence of affordable prepaid phones is helping to alleviate this issue.