DEVICE ADVICE: Market research group IDC estimates that $7 billion worth of devices were sold to K-12 and higher-education markets in 2014. Of the 13.2 million devices shipped, Microsoft continues to lead with 4.9 million Windows devices sold, followed closely by Apple’s 4.2 million devices and Google’s 3.9 million Chromebooks. “Even if Microsoft is No. 1 in volume and Apple is No. 1 in revenue, from the growth perspective, nobody can beat Chromebook,” IDC analyst Rajani Singh told The New York Times. According to her estimates, Chromebooks already outsold Windows devices in the first half of 2015.