Amazon has announced the Kindle Fire HDX, an updated range of tablets with higher resolution HD screens, a new design and live, video tech support available though the tablet itself.

Amazon Kindle Fire HDX
The Kindle Fire HDX tablets are is available in 7in and 8.9in versions. (Amazon)

Sitting above the year-old 7in Kindle Fire HD - which receives a minor update and price drop - the new HDX range offers two tablets with 7in and 8.9in displays, each with screen resolutions higher than the Retina Display of the newest iPad.

However one of the most interesting new additions is what CEO Jeff Bezos says will "revolutionise tech support."

Mayday is a virtual help service where an Amazon employee will appear on the screen of your Kindle Fire within 15 seconds of pressing the help button. The support person will be able to take full control of your device to help you fix whatever problem you're having.

Amazon stresses that the employee cannot see the user through the device's cameras.

The 7in HDX is priced from $229 for the 16GB Wi-Fi only model with Special Offers (adverts on the lock screen), while the 8.9in HDX starts at $379 for the same configuartion. The HDX range will start shipping in mid-October, with the full range available in time for Christmas. We will update this story when UK prices are made available.

Standout

The screens are the standout feature of the new Fire range, with the 7in model boasting a resolution of 1920 x 1200 and pixel density of 323 pixels per inch (ppi), while the 8.9in version has a resolution of 2560 x 1600 pixels giving it a a pixel density of 339 ppi - beating both the iPad mini (163ppi) and iPad with Retina Display (264ppi).

Amazon claims the Fire HDX range has perfect colour accuracy and "dynamic image contrast" which adjusts the contrast of each pixel depending on the ambient lighting, making reading in bright sunlight more comfortable.

Almost identical in terms of hardware, the two Fire HDX models are powered by quad-core 2.2GHz Snapdragon 800 processors with 2GB of RAM and Ardeno 330 graphics for gaming. Amazon claims the tablets have three times the performance of last year's Kindle Fire, double the RAM and four times the graphical power.

The retailer promises battery life of 11 hours for each model, or up to 17 hours if you're just using the device to read.

Design quirk

Both models have a plain black front with glass covered screen and HD front-facing camera, while around the back Amazon has given the tablets a design quirk in the form of an angular band along the top edge, housing a rear HD camera and flash. Amazon has also relocated the power and volume buttons to the back.

Like last year's model, the Kindle Firs HDX range will run a heavily modified or forked version of Android, surfacing the retail giant's own app store, music store and LoveFilm streaming service.

The newest version of this Kindle operating system, called Fire 3.0 Mojito, is new for the HDX range and brings changes such as no longer making the home screen carousel of content mandatory, replacing it with an optional grid view if you prefer.

There are also updates to the email, calendar and document-editing applications, more enterprise support for business users and extra tools to help the visually impaired.

Modification

Due to its heavy modification, Amazon's Kindle OS is not Google certified and therefore doesn't support the official Google Play Store.

New for the HDX range is the ability to download Prime Instant Video content and watch it offline, essentially giving users access to an enormous film collection to view wherever and whenever they like. Each HDX tablet comes with a free month of the Prime service - with the service costing £49-a-year otherwise.

There's also an update to Amazon's X-Ray feature, which adds music and video content to its repertoire. X-Ray will show lyrics of the track you're listening to, and can identify music played in the background of films and TV programmes you are watching, along with trivia about your video content, backstories for the characters, and other information gathered from Amazon-owned IMDB.