An iOS app where you write down 5 things you're grateful for each day. Similar apps are available for Android.
Flickr Creative Commons Photo: Run for Kika
RunKeeper uses the GPS feature on mobile phones to track exercise routes. Track distance, altitude, calories, and more.
Flickr Creative Commons Photo: kensavage
Fitocracy is fitness "gamified." Keep track of fitness activities and earn points and badges. Use social networks to keep motivated.