I was a big fan of this app, having previously found it more accurate and convenient even than calling airlines directly, until I used it to track an important international flight. The app consistently registered that the flight would arrive 9 minutes later than its scheduled arrival time, when in fact the flight landed 55 earlier than the scheduled time. Im back to calling the airlines, and will only use this app--if I use it--as a novelty.
Charlie Lima Tango about FlightAware Flight Tracker, v5.2.1