Party with a Local - Party with a Local is a free app that connects travelers with locals that want to party.
Sygic Travel Maps - Itinerary planner for independent travelers
Palaround - Meet people you should be friends with.
Detour - Immersive audio walks, now in 17 cities
Project Fixup - Meet people, not profiles
Foursquare 10 - Your ultimate city guide, in your pocket