According to a patent filed four months ago, Apple appears to be working on an activity sensor aimed at skiers, snowboarders and mountain bikers. Similar to the Nike + iPod and MotionX concept mentioned here earlier, a sensor attached to a boot or bike would determine the amount of air time and height, speed, activity time, distance traveled and power output of the wearer.
The key differentiator in the Apple patent is air time or loft which is yet to be measured in any application. "A loft sensor senses a first condition that is indicative of the vehicle leaving the surface, and further senses a second condition indicative of the vehicle returning to the surface," the patent filing explains. "A microprocessor subsystem, e.g., a microcontroller, determines a loft time that is based upon the first and second conditions, and the loft time is thereafter displayed to a user of the apparatus by a display, e.g., a LCD or LED display."
The activity sensor is a prime example of Apple grabbing an idea developed by a third party and taking it up a notch. I always thought that the "open" App Store was simply a testing ground for Apple and if a third party application proved to be popular, Apple would develop and market their own, improved version.