Both devices are powered by a 2.2GHz Snapdragon 800 quad-core processor, which the firm said has three times the power of its older Kindle Fire HD tablets. Both devices also have an 8MP rear-facing camera and a front-facing camera for Skype video calls, of 720p HD quality.
Both devices come with storage options of 16GB, 32GB or 64GB and have WiFi-only or WiFi and mobile data connection options. Pricing starts from $229 for the 7in device in 16GB through to $579 for the 4G, 64GB 8.9in version.
Perhaps the most noteworthy addition to the devices, though, is a new Mayday feature that allows users to video call an Amazon tech support assistant, free of charge, to allow them to take control of the device or provide direct instructions to fix issues or show how the tablet works.
Amazon also said the devices would come with a new version of the Fire operating system called Mojito, which will offer a raft of enterprise-grade features. These include WPA WiFi network support and a built-in suite of tools for documents, spreadsheets and presentations.
Native VPN client support and hardware data encryption are also included on the Kindle Fire HDX, Amazon said. The firm will also launch a Fire 3.1 over the air update for existing Kindle devices around mid-November, which will include a number of these features.
V3 contacted Amazon for UK pricing and availability of the new devices and to confirm if the software update would be launched in all markets, but had received no information at the time of publication.
The device is the latest tablet announced by a major retailer in the start of the run up to Christmas, with Tesco announcing the Hudl device, costing just £119 as it enters the tablet fray.
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