Trip Advisor City Guides
Cost: Free Trip Advisor, known primarily as a hotel reviews site, recently launched a series of free guides for cities including New York, Barcelona, London, Paris and Las Vegas. The guides include reviews of restaurants, attractions and hotels, as well as information about neighborhoods, culture, architecture and transportation. We loved the self-guided tours of attractions like a walking tour of the Brooklyn Bridge and the Financial District, which give tourists step-by-step instructions (complete with photos) of the best way to view these landmarks and their surroundings. Our favorite part of the app: You don't need a working data connection, as all of the content is already stored within your phone.