You just might find the best travel apps under a different category.

Currently there are over 10,000 apps dedicated to travel in the iTunes store. Browse through the travel section and you’ll find an app for almost anything travel related; most of the major airlines have their own apps as do travel agencies like Kayak, and car rental outlets like Avis. All of them useful.

But often the apps I find myself using for traveling are those you don’t find in the travel section. You find them under categories such as productivity, social networking or books, although you might not think of “travel” when you first look at them.

These are ten apps that I find most useful.

Kindle and Stanza

Amazon has made the Kindle available for the iPhone and it’s fully customizable so reading even on this small screen can be comfortable for anyone. Carry a small library wherever you go to keep up on your reading.

Likewise, with Stanza, download free books from public domain sites such as Project Gutenberg to help enhance any travel experience. Now reading the Hunchback of Notre Dame while sitting in a café in Paris or Marco Polo’s journals while traveling through Asia is as simple as reaching into your pocket.

Price: Free

Skype

Call your friends and family, heck call a stranger. As long as they have Skype, it’s free from anywhere in the world. You can also call a landline or cell phone for just a minimal charge. For the iTouch, headphones with a mic are required but it’s still easier and a lot cheaper than renting a cell phone.

Price: Free

The PDF Reader

It’s not something you instantly look at and think of travel, but I find it indispensable while traveling. Download any pdf file from your computer or from within the app itself and have it available for offline viewing.

Things I download? Neighborhood maps, subway maps, Wikipedia pages, Google directions, recipes, articles…you get the idea. Added bonus is the space you save not having all of those individual subway/map apps cluttering your iTouch. Additional plus for the iPhone is the battery usage you save not going on 3G.

Price: $0.99

Ambiance

Download from hundreds of free sound clips in their database and create your own environmental mixes. Perfect for drowning out noise and helping you to relax or sleep.

Wolves, rain, birds, trains, white noise, mix ‘em and create your own perfect relaxing atmosphere. Two mixes I’ve created are called Desert Campfire and Rainy Lakeside Cabin. I’m relaxing already.

Price: $0.99

AppBox Pro

This app has a Currency Converter, a Unit Converter, a Translator, a Tip Calculator, a Flashlight, a Ruler, an app for International Holidays and that’s not even half of the programs contained within. Plus it frees up a lot of space by consolidating these frequently used programs into one app.

Price: $0.99

Tweetie 2

Twitter as a travel app? You betcha. A lot of the big name airlines offer special deals only to their twitter followers. Travel writers tweet their discoveries and local specialty food trucks in New York and LA tweet their locations.

If you want to know anything about a place, how to get there, or what to do once you’re there, Twitter is quickly becoming the way to do it. Added bonus, Tweetie 2 was just purchased by Twitter to be their official app. In a few weeks it will appear sleeker with a price drop to “free.”

Price: $2.99

Momento

Make journal entries easily while this app also downloads your activity from Twitter, Facebook, Flickr and Last.fm as part of your daily journal. A great app for recording all aspects of your travels as they happen and keeping them in one place.

Price: $2.99

Star Walk

Now no matter where you are, you can locate the planets or the constellations, be informed of meteor showers, anything needed to turn you into an amateur astronomer. An added bonus is that it’s perfect for bringing everyone together around a campfire.

Price: $2.99

myLanguage and myLanguage Pro

Type in any word or phrase and get a translation in 53 different languages. The main difference with the Pro version (besides price) is that it will actually speak the translation in audio form. The only issue is Wi-Fi or 3G is needed to connect to their database for use. Still I’ve still found it indispensable.

Price: Free (Pro Version – $4.99)

ooTunes

Listen to NPR in Greece, the BBC in Kentucky, KCRW in India. A great internet radio app that has access to virtually any station with web play. Added bonus: it automatically records everything you listen to for easy replay later.

Price: $4.99

Community Connection

Looking for more travel apps? Check out 10 Cheap (Or Free) iPhone Apps For Travelers and iPhone Apps for Freelance Writers.