This year vendors will ship 1.1 billion devices based on Android, while Windows stages a small comeback and the number of Apple machines, percentage-wise, increases the most, according to estimates from market research company Gartner. Shipments of PCs, tablets, and mobile phones of all shapes and sizes will increase by 7.6 percent year-on-year to 2.47 billion units, as users across the globe continue to buy more tablets and phones, according to Gartner.