SAN FRANCISCO -- Roku is getting into an Internet video-streaming fight with Google's Chromecast.
Like the similarly shaped Chromecast, Roku's thumb-size device plugs into a TV's HDMI port and feeds Internet video through a Wi-Fi connection.
The Roku device, announced Tuesday, sells for $50 compared with $35 for Chromecast. The low price and Google brand cachet have made Chromecast popular since its release last summer.
Google hasn't divulged Chromecast sales, but the stick ranks as the second-most-popular electronics item on Amazon.com. Only Amazon's own Kindle Paperwhite e-reader outsells Chromecast in the website's electronics section.
Some of Chromecast's sales may have come at the expense of Roku's line-up of set-top boxes for showing Internet video. The latest box, the Roku 3, sells for $99 and ranks fifth in Amazon.com's electronics sales.
Overall, Roku says it has sold more than 8 million video-streaming devices since its first box hit the market nearly six years ago. The privately held company, which is based in Saratoga, doesn't disclose its financial results.
Roku has been selling another video-streaming stick since 2012, but that device works only on TVs with mobile high-definition, or MHL. TVs with an MHL port are still a specialty item. Virtually all TVs sold in the past few years have an HDMI outlet, widening the appeal of the new streaming stick.
Although Roku's HDMI stick costs more than Chromecast, the company is counting on its broader selection of apps to give it an edge with consumers. Roku has more than 1,200 apps, or "channels," that stream video, such as Netflix, HBO Go and Hulu Plus, as well as apps from Major League Baseball and the NBA. It also has music and photo services. Chromecast lists 14 apps on its site, including Netflix, HBO Go and Hulu Plus.
Amazon.com and several other sites are accepting pre-orders for Roku's new stick for delivery next month. The device also will start showing up in stores then too.