Kwikset's new Kevo door lock turns your iPhone into the simplest of digital keys. Just have your phone in your pocket or purse, tap the Kevo lock, and you're in.

We first saw the Kevo on ABC's Shark Tank when UniKey CEO Phil Dumas pitched the idea to the program's investors. He convinced Mark Cuban and Kevin O'Leary to hand over $500,000, then parlayed his 15 minutes of reality TV fame to raise another truckload of cash. Dumas eventually caught the attention of Kwikset, which partnered with him to make his dream a reality.

This thing is incredibly cool. The Kevo looks like an ordinary lock, but the halo of light surrounding the keyhole gives it a vaguely futuristic look. An app links your iPhone (sorry - no Android) to the lock using Bluetooth and the miracle of location services, eliminating the need to fumble through your pockets or purse for your keys. Just tap the lock with your finger and the halo flashes green, letting you know the door is unlocked. You don't even need to take your iPhone out of your pocket.

Those of you with families or roommates will, of course, need more than one iPhone key, so the Kevo app lets you create electronic keys for other people. (Just remember they'll need iPhones too.) It's also a handy feature for giving, say, dog sitters or contractors access. As soon as they're done with their work, just delete their key.

The Kevo knows when you're inside, too. That way, some random creep walking down the street can't simply tap the lock and wander in while you're in the shower. This being 2013, the lock has various levels of encryption, making it difficult (though not impossible) to hack. Using Bluetooth and location services will probably suck your battery down with some haste, but Kwikset swears it won't be a drastic drain. The Kevo lock runs on two AA batteries good for about a year, according to the company.

If you're among the millions who haven't drunk the iPhone Kool-Aid, don't worry. You can still use the Kevo lock with the Kevo Fob. It does basically the same thing as the iPhone and app, but you only get one fob per lock. If you live with multiple people, you'll need to shell out extra cash for more fobs. The lock is expected to come out this summer.

And if all else fails, Kevo can still work like a traditional door lock. But what's the fun in inserting and turning a physical key on lock like this?