Smile! It’s the quickest way to unlock your phone.

Straight out of sci-fi, Google and Samsung unveiled an unlocking mechanism based on facial recognition as one of several new features of the long-anticipated Galaxy Nexus. The companies showed off the new phone — the first to come with Android 4.0, Ice Cream Sandwich — late Tuesday at an event in Hong Kong.

Galaxy Nexus users will be able to do away with passcodes and other security measures, though the phone itself warns you that it’s not exactly the best option. In Google’s introduction video, a screenshot of the phone says the feature is “low security, experimental.” The feature didn’t work in Google’s on-stage demonstration, either: while the phone didn’t unlock when it saw a stranger’s face, it didn’t seem to recognize its owner, either.

The Galaxy Nexus has a ton of other features as well, including voice typing, baked-in Google+ integration with hangouts and Messenger and the ability to take a panoramic photo with a single motion. Some were disappointed that the phone didn’t have the drastically curved profile Samsung hinted at in its promotion images for the phone, though the new phone sports the same “contour design” of the Nexus S.

Other specs for the phone include a slightly slower-than-expected 1.2 GHz processor and a “high-end” camera with a 5MP resolution. As CNET’s Jessica Dolcourt pointed out in her hands-on writeup from the event, that spec is a little puzzling, since Samsung has put 8MP cameras in its Galaxy S line. Then again, the companies said that this phone has better camera software, which may make up for the lower resolution.

And, because the phone is running on Ice Cream Sandwich, it ditches the hardware buttons that line the bottom of every Android smartphone in favor of software buttons, giving customers more use of the 4.65-inch screen.

The companies didn’t make any official pricing announcements, though an anonymous tip to Engadget set off speculation that the phone will hit Verizon’s network for $299.99 with a two-year contract. You can take that estimate with a shaker of salt, but it would bring the Galaxy Nexus in line with the prices of other premium phones on the network, such as the Droid Bionic.

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