Name: LoungeBuddy

Available for: iPhone and iPad

Cost: Free

What it does: Details everything there is to know about airport lounges, including day-use costs and amenities, as well as photos and reviews. Includes 600 lounges at the 60 busiest airports in the world.

What's hot: This user-friendly app goes way beyond a general list of lounges. After LoungeBuddy asks you a few simple questions about your route and current memberships, credit cards and loyalty programs, it provides you with a list of lounges best suited to your trip. You can quickly filter for lounges that are free to you, have Wi-Fi, free cocktails and showers, children's rooms and more. I found the user reviews most helpful, especially those who shared that they found fast Wi-Fi, dirty areas or quiet corners. Create a free profile with your email address to start reviewing lounges yourself.

What's not: If pushed, I'd say that it would be nice to have a visual clue for lounges that let you invite guests for one fee and a filter that lets you know which lounges are open. Maps of terminals and lounges are coming soon.

Worth it? It would be silly not to see which free amenities are available to you. Also worth noting - it's designed for iOS7, but I tested it in iOS6 on an iPhone 4S.