FlightView Free Flight Tracker This app is a real time flight tracking device. When you select your flight you can save it in My Trips. You can receive instant alerts when a status changes. You can view national airport delays with weather too.
FlightStats Lite for Android A free tracking application where you can save your searches. You can see the results of your flight stats online as well.
FlightTrack This app lets you see status' for gates, delays and cancellations. It covers more than 4,000 airports worldwide too along with the 1,400 international coverage. Just in you can look for alternate flights. This can become a widget too.