Western Digital Western Digital reportedly earned its number one title by focusing on the rapidly expanding mobile sector, whereas Seagate catered more to desktop and enterprise customers. The mobile computer market grew by 29% in 2010 -- more than triple the desktop sector's 8% increase. Western Digital accounted for 27.5% of mobile drive shipments, followed by Hitachi at 26% and Seagate at 20.4%. With the emergence of tablet PCs, 2011 should prove to be another fruitful year for the mobile storage market.