A number of Lonely Planet travel apps for iPhone are currently available free. These are for cities in the US and Canada including New York, LA, Las Vegas, Vancouver, and Seattle. Get them while you can as the offer runs out Friday 4th Feb (today). They did the same thing just before Christmas when they made a number of European city guides available for free. Even if you're not planning on travelling any time soon I'd recommend getting them as the apps are kept up-to-date so will be useful whenever you get chance to make that dream trip!
See the full list at http://www.macworld.com/appguide/browse.html?collection=6546