Foursquare City Guide - Foursquare City Guide is a Free to use mobile application that will lead you to the perfect spot anytime anywhere around the world.
Wikivoyage - the free worldwide travel guide that anyone can edit.
Journy - Tastemaker-driven concierge to plan your perfect trip
Tripadvisor - The Tripadvisor mobile app is available for the Android and iOS platforms. It can be used to create reviews of hotels, restaurants, and to chat with other travelers on Tripadvisor forums.
Flamyngo - Create a city guide with help of your friends.
Triptipedia - Triptipedia is a free collaborative encyclopedia of travel tips, where everyone can browse, save and share tips for better travel!