Roku (ROKU -0.32%) and Amazon (AMZN 0.03%) are the two biggest players in the streaming hardware space. With all due respect to Apple's Apple TV and Alphabet's Android TV, the Roku and Fire TV platforms are the dominant ones in streaming. Customers get access to those platforms by buying Roku and Fire TV set-top boxes and streaming sticks -- or, increasingly, by buying smart TVs with the platforms already built in.

Roku has been partnering with manufacturers like TCL to make its smart TVs since 2014. Amazon came to the game a bit later, in 2017, but it has attacked the same market with partners like Toshiba. And Amazon is now selling TVs with an added feature that Roku's had for years, making its latest smart TV models look very competitive with Roku's popular low-cost 4K HDR TVs.

A hand holding a remote control aimed at a TV.

Image source: Getty Images.

Amazon steps up

Amazon's Fire TV smart TVs have offered 4K resolution for a while a but until recently, Amazon's TVs couldn't support HDR (high dynamic range), which, in the context of imaging, means a greater capacity for contrast and larger ranges of color. That means that TVs with HDR have deeper and more brilliant colors -- darker blacks, brighter whites, and more shades in between.

The lack of this in the past led to some lackluster product reviews. Roku's various lines of Roku TVs, on the other hand, have boasted HDR options for years.

Amazon's latest Toshiba Fire TV Editions are running at pretty reasonable price points: There's a 55-inch model for $449.99, a 50-inch one for $379.99, and a 43-inch one for $329.99, according to a June 20 report from The Verge.

That's right around where Roku's TCL series is priced. The 55-inch, 49-inch, and 43-inch TCL Roku TV models that boast Dolby Vision HDR (which is the same brand of tech used in the new Fire TV Edition models) cost $499.99, $319.99, and $259.99, respectively. (This is not an exhaustive list of Roku's smart TV offerings; I'm focusing on the low-cost TCL models.)

Cheap HDR and the 4K tipping point

It's about time that Amazon offered better TVs to customers at this price point. Though Amazon's older models weren't always expensive, they didn't offer this kind of tech -- and that made Roku's TVs a better deal. But the fast-dropping prices of HDR technology (which mirror the dropping prices of 4K technology) made this moment inevitable.

We're well past the 4K tipping point. 4K Ultra HD is now pretty much industry standard on all TVs and HDR is fast becoming an expectation at moderate and low price points, too. It's easy to see why Amazon needed both to continue its battle in the affordable streaming space.

Roku and Amazon have been at each other for a while in this space. Late last year, Roku released the cheapest 4K streaming stick ever. As the cost of this sort of technology has come down, features -- not price -- have come to define the low-cost streaming race. A customer can get a decent streaming stick for less than $50 and a decent smart TV for around $300; the question is what those devices can do.

The hardware front of the platform war

Amazon's somewhat disappointing early TV efforts have not done enough to help it keep up with Roku. Analysts at Strategy Analytics say that 30% of all connected TV devices sold in Q1 of 2019 had Roku's platform on board, while only 12% sported Amazon's Fire TV platform.

And Amazon really, really wants to gain decent market share in the platform race. Amazon's Amazon Video service and streaming video marketplace compete with the likes of Netflix and iTunes, but Amazon has a massive advantage over those competitors with every user of a Fire TV device because on the Fire TV platform, Amazon's own offerings are surfaced. Amazon is trying to monetize its platform primarily by using it to direct users to Amazon's other services.

That only works if people use Fire TV devices, though. Amazon will hope that its best low-cost smart TV yet will help turn the tide in its battle with Roku.