Amazon is secretly developing a range of gadgets, including two different smartphones and an audio-online streaming device, for its Kindle line of hardware, according to the Wall Street Journal.

The most buzzworthy product is a high-end smartphone that features glasses-free 3D viewing. It reportedly used eye-tracking technology to make holograph-type images appear three-dimensional from all angles. R2-D2’s famous projection from “Star Wars” immediately comes to mind:

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"Help me Amazon, you're my only hope." Courtesy / 20th Century Fox

Last year, rumors about Amazon building a smartphone materialized, and last month it was reported that the Seattle-based "e-tailer" was building a set-top box.

It seems as though the earlier leaks are merely part of a master plan to offer an extensive line of tech hardware, some or all of which could be shelved indefinitely, the WSJ reported.

Are glasses-free 3D and holographic smartphones something you'd shell out money for? Which features would you like to see in an Amazon smartphone? Let us know in the comments section below.

Here's an obligatory photo of Jeff Bezos' shiny head:

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Reports that Amazon is expanding its Kindle line beyond tablets and e-readers are increasing in number. Courtesy / Reuters