According to a report from Canalys, Apple was the largest company in the PC and tablet markets in Q4 2013. Apple shipped 30.9 million Mac and iPad units, making the company have nearly 20 percent share of the market (19.5 percent). Lenovo is rising considerably, and is now at second spot (11.8 percent). They’ve increased their market share by 25.5 percent year on year.
The iPad was responsible for a lot of those sales, with Canalys estimates placing it at 84.3 percent of the shipments (26 million units). This is partially because of the recent update to the iPad range, boosting sales but the iPad range always sells more than the Mac range nowadays.
Apple had 34.1 percent of the overall tablet market in Q4 2013. The report didn’t disclose how much of the premium tablet market Apple had. This is partially why they ‘only’ had roughly a third of the market: cheap Android tablets like the one in Walmart's $49 promotion sell well, despite not performing well. Canalys did mention this in the report: “But competition is mounting and Android tablets are falling in price, which will put pressure on Apple’s market share in 2014.”