Flighty

Official Page

The best flight tracking app I've used. It pulls data from multiple sources and will often know about delays and gate changes before the airline's own app does. I've had a few trips where I would have been stuck at the wrong gate if not for Flighty catching a last minute change.

The UI gives you a clean timeline of your flight with everything you'd want at a glance like gate, terminal, baggage carousel, and seat info. You can also see where your actual plane is coming from which gives you a real sense of whether your flight will be delayed before it's officially announced.

It's a premium app with a subscription but if you fly more than a few times a year it's well worth it. The free tier still gives you solid tracking for a single flight at a time.