It's nice to be able to use the app as an e-ticket, but twice I have had the return leg of a round trip disappear after the outbound leg is complete. To get it back I would need the reservation number, but of course that is on the vanished e-ticket. I'd like to be able to use this, but I've taken to printing the e-ticket PDF or opening it in iBooks on my iPad. Either one works, but seems to defeat the purpose of having the mobile app. Anyone else have this problem?