So Virgin Australia and a lot of other low cost airlines allow you to rent an entertainment device for your flight. This is in contrast to say Air New Zealand which has in seat entertainment. This opens up low cost airlines to competition from a company at an airport that would rent iPads or other entertainment devices for a nominal fee, and then have them returned at the other airport, say the Auckland to Sydney route.
This is a business opportunity for someone interested in loading an iPad full of fun games and content, charging people a nominal fee to rent it, say $20 NZD for three hours. You could get $60NZD a day, or $21,900 a year (365 days a year). Break even would be @ 40 flights, or two weeks.