Apigy this week began taking pre-orders for the Lockitron, a keyless device that allows users to unlock their doors with only a smartphone. Equipped with Bluetooth 4.0, Wi-FI, and NFC capabilities, the Lockitron is a battery-powered box that attaches to a door's deadbolt. Users can unlock their doors by either swiping their NFC-enabled phones against the Lockitron, or, if their handsets include Bluetooth 4.0, by simply walking up to the door.

The Lockitron originally began as a Y Combinator project in 2009, but has since become more accessible. Previously, users had to fully replace their deadbolts, whereas the latest version slides under existing locks. You can control access via the Lockitron smartphone app (available on Android or iOS), allowing you to remotely grant or revoke access from anywhere in the world. The device's built-in knock sensor will alert you whenever anyone is at your doorstep, and if you misplace your phone, you can always disable your account by remotely changing your password. The Lockitron app will also send you a text message whenever anyone unlocks your door, even if they use a key.

Apigy's device joins a growing market of keyless locks. Schlage unveiled its web-based Z-Wave back in 2008, while Yale announced a similar, NFC-based system last year. The Lockitron is available now for $149 on pre-order. According to AllThingsD, the device is expected to ship in March, though users won't be charged until it's ready for delivery.