Yelp, the iPhone's most popular place finding and reviewing application, has just added a new feature. And it's "secret", probably because it's not perfected yet. The new feature, dubbed Monocle, turns Yelp into an Augmented Reality application. The feature only works for iPhone 3GS owners, because it requires the compass.
To activate the feature, open yelp and shake the phone three times.
Monocle is now activated. The feature puts whatever the camera sees on the screen, and overlays it with icons of Yelp reviewed locations. Each icon includes the rating, the distance, the direction, business type, and price level. It's extremely cool, and surprising…Augmented Reality applications weren't supposed to come out until iPhone OS 3.1.
It works well, except the compass tends to give problems. It constantly says that the compass needs to be calibrated, even after you calibrate it. And sometimes it's still off by 15 degrees or so after you calibrate it. This is not Yelp's problem, this is related to issues with compass on 3GS.
We'll let you know when Yelp actually announces the feature. While your all Augmented-up, check out this article of all the iPhone AR apps out there. In addition, Paris Subway app has augmented reality functionality.