Worldwide Tablet plus 2-in-1 Shipments, Market Share, Year-Over-Year Growth by Operating System, 2014 – 2018 (Shipments in millions)
| Operating System | 2014 Shipment Volumes | 2014 Market Share | 2015* Shipment Volumes | 2015* Market Share | 2019* Shipment Volumes | 2019* Market Share |
| Android | 154.7 | 67.3% | 158.1 | 67.4% | 169.5 | 62.9% |
| iOS | 63.4 | 27.6% | 60.1 | 25.6% | 61.9 | 23.0% |
| Windows | 11.6 | 5.1% | 16.3 | 7.0% | 38.0 | 14.1% |
| Total | 229.7 | 100.0% | 234.5 | 100.0% | 269.4 | 100.0% |
Source: IDC Worldwide Quarterly Tablet Tracker, March 12, 2015
IDC has scaled back its five year forecast for the tablet category. They expect tablet shipments to reach 234.5 million units in 2015, a modest year-over-year increase of 2.1% from 2014. They think that Microsoft will slowly gains a foothold in the tablet market. Windows, despite modest adoption to date, is expected to gain significant share over the course of the forecast, growing from 5.1% in 2014 to 14.1% in 2019.
“Microsoft is doing a lot of good things right now and we believe the launch of Windows 10 later this year will not only have a significant impact on Microsoft’s share of the market, but on the industry as a whole,” said Jean Philippe Bouchard, Research Director, Tablets. “There is an appetite for a platform that can provide a productivity experience that remains consistent across multiple form factors and device types, and we believe Microsoft is well positioned to capture some of that demand.”
Source: IDC