Smartphone market saturation is fast approaching, but a winner may step forward once the dust settles after all. According to IDC, despite 39.2% growth in 2013 (the year of 1 billion smartphone shipments) every major OS will begin to gradually shed its market share over the next four years — every OS except for Windows Phone. As the developed markets hit saturation, OEMs with a plan to reach maturing markets will have the most room for growth. Microsoft has already positioned Windows Phone as the OS for the rest of the world, a move that could pay dividends as the decade comes to a close.

“In order to reach the untapped demand within emerging markets, carriers and OEMs will need to work together to bring prices down,” said Ramon Llamas, Research Manager with IDC’s Mobile Phone team. “Last year we saw a total of 322.5 million smartphone units ship for under $150 and that number will continue to grow going forward.”

Take a look at the following chart to get a better idea of where the major operating systems will stand in 2018: