Nook HD tablet
The new Nook HD tabletReuters

America's largest book retailer Barnes & Noble on Wednesday launched its new Nook HD and Nook HD+ with an aim to takeover the e-reader market from arch rival

The new Nook versions run on modified versions of Android 4.0 OS and provide a unique multiuser platform wherein every user can create their own account. Each user can disable or enable different features in each profile, while being able to password protect the account.

Nook HD sports a 7-inch screen resembling the earlier versions like Nook Tablet and Nook Color, while Nook HD+ comes with a slightly bigger screen at 9-inches. The 7-inch slate is up for a price of $199 and the 9-inch version is priced $269.

Nook HD packs a 1.3GHz dual core OMAP 4470 processor and has 720p video playback support. It also comes with 1 GB of RAM and 8GB of internal memory that is expandable up to 16 GB. The device is powered by a 4050 mAh battery, which the company claims will give 10.5 hours of reading or 9 hours of video playback. It also features Wi-Fi and Bluetooth connectivity options.

Nook HD+ packs the same processor as Nook HD but with a beefier 6000 mAh battery. It come with 1GB of inbuilt storage and has either 16GB or 32GB of onboard memory. Besides WIFI and Bluetooth, the device has other features like stereo speakers and Full HD video output.

"We are playing in the tablet space, but reading is at our core," Barnes & Noble Chief Executive William Lynch told Reuters in an interview on Tuesday.

At 315 grams and 515 grams, Nook HD and Nook HD+ are lighter than Apple's new iPad which weighs 652 grams for the Wi-Fi- only version. Both devices will have access to Nook video services and can get access to Nook cloud service as well.          

The two tablets will be in direct competition with Amazon's popular Kindle Fire HD, which sports an 8.9-inch -inch screen, a 1.3-megapixel primary camera and costs as high as $499 for 32 GB model. On the downside, Nook HD and Nook HD+ lack cameras.

The devices will be up for sale in the US market this November.