In addition to launching the anticipated and so-called iPhone 5S and iPhone 5C devices next week, Apple is understood to be testing new form factors for iOS, including a 4.8-inch larger screen smartphone and a 6-inch phablet device.
According to the Wall Street Journal, Apple is more willing than ever to explore a multi-device strategy after losing considerable ground to Korean electronics giant Samsung, which this week unveiled the Galaxy Note 3 with a 5.7-inch screen.
Component suppliers claim Apple has already begun testing larger screens for iPhones in recent months.
Apple last year expanded the screen size of its smartphones from 3.5 inches on the iPhone 4S to 4 inches for the iPhone 5.
On Tuesday next week, Apple is expected to unveil a next-generation iPhone 5S with fingerprint technology and a low-cost polycarbonate-clad device called the iPhone 5C, which will come in several colours.
According to IDC’s latest smartphone market analysis, iOS devices currently command 13.2pc of the global market down from 16.6pc a year ago, while Android has grown from 69.1pc to 79.3pc of the world smartphone market.