The firm expects mobile phone shipments to touch 1.81 billion units this year against to 1.74 billion units in 2012.
"The mobile phone market will continue to experience steady growth, but the opportunity for high average selling price (ASP) smartphones is now ending," Gartner said, while giving its global outlook for the PC, tablet and mobile phone shipments.
The firm added that growth is expected to come from mid- tier smartphones in mature markets and low-end Android smartphones in emerging markets, like India.
Worldwide combined shipments of devices (PCs, tablets and mobile phones) are projected to reach 2.32 billion units in 2013, a 4.5 per cent increase from 2012, it said.
"The market is being driven by a shift to lower-priced devices in nearly all device categories," Gartner said.
Android will remain the leading device operating system (OS), as it is on pace to account for 38 per cent of shipments in 2013, it said.
Windows OS is projected to decline 4.3 per cent in 2013 as a result of the decline in traditional PC sales, but will return to growth in 2014 with device OS shipments increasing 9.7 per cent, it added.
Similarly, another global research firm IDC also said that mobile phone shipments will increase aided by sub-USD 200 smartphones.
Worldwide smartphone shipments are forecast to grow 40 per cent year-over-year to more than 1 billion units in 2013.
"High smartphone growth is the result of a variety of factors, including steep device subsidies from carriers, especially in mature economic markets, as well as a growing array of sub-USD 200 smartphones," it added.
Total smartphone shipments are forecast to reach 1.7 billion units in 2017, IDC said.
Overall mobile phone market is growing faster than previously forecast thanks to a stronger-than-expected first half of the year driven by strong gains in emerging markets like India and the sub-USD 200 smartphone segment.
"IDC previously projected 5.8 per cent growth for the year. Vendors are now forecast to ship more than 1.8 billion mobile phones this year, growing to over 2.3 billion mobile phones in 2017," the research firm said.