Did you check in on the Android version of the application first and then pull that same itinerary on your iPhone? If that is the case, you will only be able to use the Android version of the application to access the mobile boarding pass.
Right now the mobile applications do not support "re-printing". By this I am referring to the idea that if you were to check in on the web and then go to your mobile application there would not be a flow for you to get the boarding pass on that device. This is something that we are looking at addressing.
Danny, eCommerce / delta.com | Delta Social Ambassador
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