Mike Segar/REUTERS
Amazon CEO Jeff Bezos
Parks Associates looked at general media device sales in the United States over the past year, and found that Roku, Google, Amazon, and Apple accounted for 86% of the overall market.
Of those four brands, the firm notes that Roku and Google's Chromecast dominated the market in 2014, accounting for 34% and 24% of the US streaming market respectively.
Apple held the third-place spot in 2013, but it recently slipped to fourth thanks to Amazon's Fire TV, which was released in the spring of 2014. Apple, meanwhile, has been selling its streaming set top box since 2007.
Here's the chart from Parks Associates:
It's also worth noting, however, that Apple hasn't released a new version of its Apple TV since 2013, so consumer attention may have shifted to newer offerings from Amazon and Roku since then.
Roku, Amazon, and Google all offer streaming options that are cheaper than the Apple TV, too. While Roku's flagship streaming box costs $99 - which is more expensive than the $69 Apple TV - it sells a streaming stick that's only $50. The Fire Stick from Amazon is only $39 (while the full set-top box launched for $99), and Google's Chromecast is the cheapest at $35.
However, while Amazon may have sold more units, it looks like people are using the Apple TV more often than Amazon Fire TV owners are using their set-top boxes. The firm's findings also revealed that Roku is the most-used streaming box at 37%, while Google's Chromecast came in second at 19%, Apple TV was third at 17%, and Amazon ranked fourth at 14%.
Apple is rumored to be working on a new version of the Apple TV that will be more powerful, will come with an interface that looks more like iOS, and will include its own App Store. It's expected to be announced in September.
Disclosure: Jeff Bezos is an investor in Business Insider through hispersonal investment company Bezos Expeditions.