Fitbit, which is the market leader in wireless activity tracking, has launched its newest tracker - the Fitbit Ultra. Priced at $99, the new gadget has a pressure altimeter that can determine when the user is climbing stairs, which will be a key metric to track if the user is trying to improve fitness by walking around.

In addition, the Fitbit Ultra will also allow users to share fitness achievments with friends, via Facebook or Twitter. This could also help users to find friends to compete with or even simply boast about their latest fitness-related achievments.

Equally exciting is the fact that there will also be a weight management tool that dynamically changes based on activities you complete during the day, called Food Goal.

The new Fitbit Ultra Wireless Activity Tracker is currently available in the U.S. and Canada, on their Web site - www.fitbit.com. Unfortunately, it will not hit retail stores before mid-October and even then be available only at select retail locations across the U.S.