The iPhone, in particular, has amassed more than 900 applications targeting business or leisure travelers. Many applications are free, and others range from 99 cents to $19.99.

Unlike desktop software, iPhone applications are relatively simple tools that don't require hours to learn. Most rely on the phone's embedded GPS chip to tailor information to a traveler's current location, such as spotting nearby Starbucks, Wi-Fi hot spot, police radar, restaurants and taxi companies. Others transform traditional travel tools — foreign language phrase books, city guidebooks, restaurant tip cheat sheets — and render them digitally.

We recently tried several of the most popular iPhone travel applications. Here's what we found: