The Augmented Reality application works turn by turn, using iPhone 3GS magnetometer, hence application is rendered useless for previous gen. iPhones.
Features: The very basic starts by choosing layers from sites like Wikipedia, Trulia real estate search, Flickr and Twitter mashups. Point your phone around you, and Layar brings up the results as blips on a planar, sonar-type screen, with a smidge of information about each one. For your records and favorites, you can tag layers, take screenshots, and get mapped directions to anything that seems far, walk towards it you will start seeing some interesting facts.
The best use case is finding food, services, and neat stuff to check out on vacation. the application proves out to be costly as you might endup buying an extra cup of coffee 😉
Layar is a free download for iPhone 3GS models, running the 3.x firmware.