Originally Posted by MSPeconomist

IME the track your bags part of the app doesn't work so well for international origins. It also seems to have lags, so that I've noticed cases where my bag doesn't appear to have been loaded at the time the aircraft's cargo doors are closed, but it's later indicated as on board and does appear at baggage claim. I also haven't done very well at using the app to see when I need to look on the belt at my destination airport.