At No. 6 on NPD's list, Hewlett-Packard weighed in at 1.4 percent of units sold. HP actually saw a gain of 1.2 percent unit shares from 2012.
The Slate series from HP runs on the Android OS and features 7-inch and 8-inch screens. Starting at a sub-$200 price point, HP's tablets were some of 2013's most affordable tablets on the market.