Rather than hand off a spare key to your visiting guests, housekeeper, or family member—which could get lost, copied, or stolen—it's easy to send virtual keys to people, granting them access for as long, or as little, as you'd like.
As for security, there's an added level of protection to keep you feeling safe. Not only does it operate independent of your WiFi, but it's powered by four AA batteries, so you won't be stuck out in the cold should your power fail. It's also equipped with a slew of features for those with trust issues: it logs a record of who's entered and exited and exactly when they did, which can be accessed remotely from your phone or computer.
Joe McGauley is a senior editor at Supercompressor. He's more than ready to ditch his overstuffed, thigh-pinching keyring.