Roku

Roku, the set-top streaming box maker, is breaking out of the living room for the first time with a service that offers paid premium channels like Showtime and Starz that you can also watch on your phone.

On Wednesday, Roku unveiled Premium Subscriptions, which will launch late this month in a phased rollout. The idea is similar to Amazon Prime Video Channels -- a place where you can buy add-on video subscriptions that let you cobble together a sort of personal bundle of internet-delivered TV with one-click purchases.

Downsides to Roku's version? It has fewer channels to choose from at a launch. (HBO is notably absent.) And subscribing via Roku won't unlock your channels' dedicated apps. So don't expect to watch shows and movies in the Starz app via Roku even if you pay for Starz through Roku. The Roku Channel is the only place you can watch them.

Now playing: Watch this: Which Roku player should you buy?

Still, this marks Roku's addition of mobile viewing for the first time, after its lifetime locked in the living room.

Roku's iOS and Android apps will be able to stream shows and movies for the first time. Until now, the Roku app served mostly as a second remote when paired to a powered-on Roku streaming device. But soon the Roku Channel, including any of your subscriptions, will be available on its mobile app in the US. Users will also be able to start a video on a Roku player or Roku TV and pick up from where they left off while on the go.

Sarah Tew/CNET

It's Roku's latest expansion beyond set-top boxes. Though the company's bread-and-butter business is its popular streaming devices, Roku has been reaching into other businesses. It's booking more advertising revenue through services like the Roku Channel with its ad-supported movies, news and sports, for example.

The Amazon video channels model is a ripe target. Amazon is quiet about how the program is faring because Amazon is quiet about everything, but one analyst estimates Amazon is one of the main ways that cordcutters are signing up for paid video subscriptions. Nearly half of Starz's direct-to-consumer subscribers may be coming from Amazon, according to BMO analyst Daniel Salmon, and HBO and Showtime may be sourcing about a third of their digital subscribers there.

(Editors' note: Showtime is owned by CBS, the parent company of CNET.)

Roku versus Amazon

There are significant differences between Roku's new offering and Amazon's video channels. For one, you won't be able to unlock the dedicated apps of services that you subscribe to via Roku, a function known as authentication. Amazon added the ability to authenticate into some of those dedicated apps last year.

Sarah Tew/CNET

The selection of channels is also slimmer. At launch, Roku is offering more than 25 subscriptions, while Amazon has accumulated more than 100. And Roku didn't list some high-profile options, like HBO or PBS Kids, among the options it will have at launch. (Neither Amazon nor Roku offer Netflix, the most popular streaming network in the world.)

It's also unclear just how "one click" Roku signups will be. Amazon Prime Video Channels is based on the premise that you're already a paying Amazon Prime member, so the company has your credit card details all set up. Roku has credit cards details for the majority of its accounts but not all, Rob Holmes, Roku's vice president of programming and engagement, said in an interview last month. (Roku declined to further clarify the proportion of its monthly active accounts that have credit cards on file.)

That leaves a portion of Roku users facing the hassle of tapping in new payment information in order to sign up for subscriptions they can get elsewhere.

But like Amazon Prime Video Channels, Roku's new Premium Subscriptions give you a one-stop hub for your subscriptions paid for with a single monthly bill.

People can sign up for seven-day free trials (or longer) using their existing Roku account information. With Premium subscriptions, Roku users will be able to browse their channel's entire catalogs. Search within the Roku Channel will be expanded, allowing people to search for keywords within the channel.

Culture: Your hub for everything from film and television to music, comics, toys and sports.

Netflix's 137M subscribers evaporate fears: Blowout quarter? It's the kind of formulaic plot Netflix loves.