This app is very unstable. It is always slow to load, and sometimes it won't load at all. It's not uncommon for it to freeze after you have started to use it, which is very problematic when you are at the gate attempting to recall your boarding pass. You simply can't trust it. Booking reservations is also frustrating. You can't enter promo codes, and it often doesn't offer the same fares (or even all the same flights) as the full web site - which is also notoriously unreliable.