Earlier today Altitude Mate passed Market Place review and will be available shorty for Windows Phone 7.
Altitude Mate is a free, advert supported, app for tracking your altitude overtime and plotting it on a chart.
You can find the app here: http://windowsphone.com/s?appid=4e12f3a8-592d-4d93-90cf-36ea83ed55e3
As usual all proceeds from this app will be donated to Action Duchenne. You can find out more about the work they do here.