Amazon has updated its Kindle Fire HD tablet to the Kindle Fire HDX. The Fire HDX tablets receive more pixels in their displays and actually offer better battery life as well.

The 7-inch Amazon Kindle Fire HD offered a 1280 x 800 pixel resolution display and 216 pixels per inch. The Fire HDX upgraded the screen to an impressive 1920 x 1200 pixel resolution display and 323 pixels per inch.

The Kindle Fire HD offers only a 1.5 GHz dual-core processor. The Kindle Fire HDX really steps up the performance by upgrading to a 2.2. GHz quad-core Snapdragon processor. That is the same processor found in the LG G2 and Samsung Galaxy Note 3 smartphones. The Kindle Fire HDX also offers 2 GB of RAM. Even with the screen upgrade and the much-improved processor, the Kindle Fire HDX still manages to get slightly better battery life than the Fire HD. Amazon says the Fire HD will get about 10 hours of mixed use battery life and the Fire HDX will get about 11 hours of mixed use battery life.

The 7-inch Kindle Fire HD did not offer a camera. Amazon probably noticed that even though it is awkward to do so, tablet users still like to take pictures with their tablets and added a front-facing camera to the 7-inch HDX model. The 8.9 inch HDX model has both a front-facing camera and a rear 8 megapixel camera.

The Kindle Fire HDX is a lighter, thinner and narrower tablet than the Fire HD. The HDX will be the easier tablet to hold during lengthy reading sessions. The Kindle Fire HD measures in at 7.5″ X 5.0″ X 0.42″ and weighs 12.2 oz. The Kindle Fire HDX measures in at 7.3″ X 5.0″ X 0.35″ and weighs only 10.7 oz., according to GottaBeMobile

A big difference between the two devices is internal storage space. The entry-level Fire HD starts at only 8 GB of space and maxes out at 16 GB. The entry-level Fire HDX starts at 16 GB and also offers 32 GB and 64 GB choices. The Fire HDX is the better option if users intend on saving big files like movies on their tablet.

The final comparison is price. The 8GB Kindle Fire HD can be purchased for just $139 directly from Amazon. Staples is currently offering a special on the 8 GB Kindle Fire HD for only $99. The 16 GB Kindle Fire HDX just dropped its price by $40 and can be purchased for $199 directly from Amazon. Best Buy is offering the 16 GB Fire HDX for $179.99 with free shipping.