Report: Apple iPhone 6 Plus to be the name of Apple's 5.5 inch handset
The source of the story, Japanese blog Macotakara, was correct last year when it leaked out the title of Apple's cheaper iPhone model as being the Apple iPhone 5c. The 4.7 inch version of the handset is expected to be called the Apple iPhone 6.
There had been reports at various times of the year that one of the models would be called the Apple iPhone Air, with speculation that design cues for the phone would be taken from the Apple iPad Air. If today's rumor is true, tomorrow Apple will introduce the 4.7 inch Apple iPhone 6, and the 5.5 inch Apple iPhone 6 Plus.
source: Macotakara (translated) via BGR