For this holiday season, Foxconn expects to produce 90 million units of iPhone 6

According to research firm IDC, Apple will release a large-screen version in 2014, but will not altogether abandon the smaller 4-inch screen version of previous models.

The research firm said iOS operating system posted its lowest positive growth for the quarter (Oct-Dec 2013) at 6.7 per cent and for the year at 12.9 per cent, under performing the overall market in both instances.

In calendar year 2013, Apple sold 793.6 million units of its smartphone operating system (iOS) against 500.1 million in 2012.

Shipments of iOS-enabled smartphones stood at 51 million units in October-December last year from 47.8 million in the year-ago period.

In 2012, Apple's smartphone operating system shipments rose by 46 per cent to 135.9 million units against 93.1 million units in 2011. For Q4 2012, shipments rose by 29.2 per cent to 47.8 million units against 37 million in the same period of 2011.

According to research firm Canalys, iOS shipments in 2011 rose by 96 per cent to 93.1 million units compared to 2010.