Here are 2 great apps for those skiers and boarders out there. Ski Report provides great snow reports from US ski resorts. It also lets skiers post their own updates on conditions so that you get the real reports of how things are on the slopes. You can find the reports for all your local resorts by using the Iphone GPS.
ITrailMap provides trail maps of all your favorite resorts.
Both of these apps are free, so try them out!