The expo floor at the Appnation Conference in San Francisco shows the diversity of the mobile application economy. Tools for developers, innovative apps and platform support are all covered in the booths. Some new apps leveraging

learning games, personalized nutrition information and world audio guides will be appearing in various app stores soon.

Motion Math is a nearly-launched suite of games to help grade school students learn fractions and other math skills. Using the iPhone's accelerometer, kids bounce the fraction ball towards the correct position on a number line. The gameplay includes a hint system that gently guides the player towards the answer.

Custom built by a nutritionist, NutriSleuth enables users to search food products according to multiple profiles and search parameters. By taking a picture of the nutritional label, much of the guesswork of label reading can be avoided. In homes where one member has food allergies, another has a medical condition, and yet another chooses a specific food lifestyle, this app does all the diet-juggling and gives the shopper a red or green light. Features include allergy severity settings and pet products. Future plans to launch cross-platform.

Bringing audio tours to anyone's mobile phone, HearPlanet finds local tours based on the handset's location. The app has global content and will soon support user-contributed tours and more platform support. Currently available for iPhone and Android, HearPlanet will also extend to BlackBerry and Windows Phones in the fall.