That would be a sizable leap from the 4-inch screen of the iPhone 5 released last year, and, at the upper end, would be one of the largest on the market. Such plans signal further that the Cupertino, Calif., company is shifting its smartphone strategy as it searches for new engines of growth, and as competition with Samsung Electronics Co. intensifies.
Nearly every mobile phone manufacturer except for Apple is offering a smartphone with a large display. Samsung recently unveiled a new 5.7-inch Galaxy Note 3. Google accidentally leaked its Nexus 5 smartphone. BlackBerry has the rumored Z30 and Nokia (Microsoft) has the rumored 1520.
While it's unclear if Apple will decide to offer the iPhone in multiple sizes, people familiar with the company's plans say "it appears more willing to move ahead than in years past". Apple is reportedly most interested in recent tests of a 4.8-inch display.
The new iPhone 5S and iPhone 5C set for unveiling at Apple's September 10th press event will still feature a 4-inch display.