Just to let you know used my I fone to testout the app everything was fine just had to show boarding pass on fone and scan it at security so no more printing it out for me
Gosh tez I would be scared to do that in case my phone let me down at security and I didn't have the printed boarding passes. Presumably you had to use mobile data (wifi) unless there is free wifi at the airport?
I think the key point here is that there is now a way around the problem of printing boarding passes when you may not have access to a printer.
Note that this is now very common. I do it all the time with other airlines. Last week with Swiss and Lufthansa.
You can store the pass (often just a QR code) in your photos, as tezmand did, or in your iPhone passbook. Works a treat and means you don't have to print or carry a boarding pass.