Terminal Maps: GateGuru (free; Android, iPhone) and iFly Airport Guide (free; Android, iPhone) provide detailed maps with passenger-submitted checkpoint wait times, user ratings, and deals for hundreds of airports worldwide.
Flight Updates: FlightBoard ($3.99; Android, iPhone, iPad) lists all arrivals and departures for more than 4,000 airports around the globe; data is refreshed every five minutes.
Airport Guides: Airports are launching their own apps. Frankfurt’s FRA (pictured; free; Android, iPhone, iPad) gives you terminal maps and flight updates; Amsterdam’s Schiphol app (free; Android, iPhone) has a guide to the extensive shopping options.
Virtual Travel Aide: If you have an itinerary with several connections, GoHow Airport (free; iPhone, iPad) lets you create a personalized profile with the information you need on each leg of your journey.