Apple Inc is said to be considering expanded screens for iPhones as well as alternative colours and budget models, Reuters reported, citing four sources.
Analysts have largely attributed the success of Apple's South Korean rival Samsung Electronics to the market leader's ability to cover wider consumer bases with a variety of models. Since the announcement of Samsung's flagship smartphone the 5-inch Galaxy S4 in March, the company has announced two variations of that model alone: the S4 mini and the S4 Zoom.
According to Reuters' sources Apple is working on at least two bigger handsets for 2014, a 4.7 inch model and a 5.7-inch model.
"They constantly change product specifications almost to the final moment, so you're not really sure whether this is the final prototype," said one source.
In the coming months, Apple is expected to launch the iPhone 5S and a cheaper plastic-based handset in a bid to capture emerging-market consumers. The cheaper phone will reportedly come in a range of colours rather than the traditional black or white iPhone offerings and Apple is said to have discussed a price as low as $99 for the handset.
A perceived lack of innovation and a wobbly iPhone 5 launch have shaved value from the Cupertino-based firm, which was the world's most valuable company less than 10 months ago. Capture of untapped markets within emerging affluent classes is now considered key to rescuing Apple's flagging growth.