Barnes & Noble on Sunday cut the prices of its Nook Tablet devices and Nook Color as it tries to gain a firmer foothold in the tablet space. The company dropped the price of the 16 GB Nook Tablet from $249 to $199 , while the 8 GB was lowered from $199 to $179. The Nook Color now goes for $149, down from $169. The price reductions underscore the challenge Barnes & Noble is faces with direct competitors like Amazon pulling ahead. Data released this month by IDC showed Apple still dominates, with a 68% share of tablet shipments worldwide in the second quarter, followed by Samsung (9.6%) and Amazon (5%). Like Amazon, Barnes & Noble wants to use its tablet as a vehicle for selling e-books and other types of digital content. So the move to both meet and beat the Kindle Fire's $199 price tag with its own tablets isn't so surprising. The bookseller is also facing new a new threat in the form of Google's Nexus 7 tablet, released in June and priced at $249 for the 16 GB model and $199 for the 8 GB version. The competition will only intensify when Microsoft introduces its Windows 8-powered Surface RT and Surface Pro tablets this fall. Pricing for those devices has not yet been released.