The airline said it will begin distributing the handsets to staff during the second quarter of 2015.
The iPhones will be used for most onboard retail transactions and will also allow workers access to corporate email, intranet, and policies and procedures manuals. The airline also plans to replace flight attendants' printed safety manuals with an electronic version on their iPhones, and provide real-time reporting and improved follow-up on aircraft cabin issues and repairs. In addition United said it plans to develop "customer-focused" tools for the device, but didn't detail what they will entail.
The deployment of the iPhone 6 Plus for United crew builds on the airline's deployment of iPads to pilots which began in 2011, in a move toward creating paperless aircraft and flight decks. More recently, United renewed the iPad pilot programme with the deployment of iPad Air 2 tablets.
Airlines are something of a growing market for tablets: both Apple's iPad and Microsoft's Surface have been pressed into service to replace paper flight manuals for pilots because they are significantly lighter than their usual luggage. For example, Delta said that rolling out Surface 2 tablets to 11,000 pilots could save 1.2 million gallons of aviation fuel per year because the slate weighed a mere 1.5 pounds compared to a traditional flight bag's weight of around 38 pounds.
Other airlines are also moving to adopt nascent technology: Virgin Atlantic, for instance, has been testing out both Google Glass and Apple's iBeacon technology at London's Heathrow airport.
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