Amazon is reportedly working on “up to five or six tablets” in different sizes, including a 10-inch tablet that could be a potential competitor to Apple’s iPad. The report comes from Reuters, which interviewed Staples retail head Demos Parneros.

The report didn’t say when the tablets would be released or even if the testing was for devices that would eventually see the market.

That’s not a lot of information to go on, but it’s no big surprise that Amazon may be planning to diversify its tablet line. The company saw success with the 7-inch Kindle Fire it introduced last October, but sales have fallen off. Competition from the Nexus 7 is has the serious potential to further hurt Amazon’s position in the tablet market, as it matches the $199 price point but offers more hardware features, such as a camera.

A new range of tablets would help Amazon keep the upper hand in the tablet wars if it can keep offering low prices for the hardware. The company should have no trouble making a profit on the Fire tablets once they get them into the hands of consumers, since it’s so easy to spend money on Amazon with the Fire.

The Reuters report also revived the persistent rumor that Amazon will release a smartphone, or at least devices that run on cellular networks, based on job postings at the company.

Amazon is seen as a sort of dark horse company when it comes to building smartphones, as the company has never made a push into cellphone hardware before but has several components in its service that would make if a formidable competitor. On the other hand, there have been plenty of skeptics who say that Amazon should think twice about jumping into a market that’s so competitive. The company has seen success in the tablet market because it can beat other competitors on price while providing basic services that it owns. The same isn’t true in smartphones, where it would face other low-price manufacturers.

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