I've been using FlightView for the past month. I travel weekly with a round trip and each trip having two legs--so four flights total. It's not bad but having used FlightTrack for so many years, I know what I'm missing. I passed along some screenshots and suggestions to the FV team and hope they'll incorporate them some day.

My pet peeves:

• I always liked the widget function that provides summary information quickly. FV shows the flight numbers but no gate or time info in the widget. Also, no calculation of the layover time
• Similarly, once you bounce to the app itself, you get detailed info about each leg, but no info about the relationship between the two. I appreciated how FT would allow you click through a flight combination, showing you the takeoff and landing times as well as gate info in a seamless stream
• The are no airport terminal maps

I spent the few bucks on the ad-free version. Still on the hunt...