DC and Warner Bros.' streaming service, DC Universe, launched five months ago and just debuted its third original program, "Doom Patrol," to critical acclaim.

The mobile app has passed 1 million installations on the App Store and Google Play, according to the mobile-marketing-insights company Sensor Tower, and has momentum.

DC Universe told Business Insider that the biggest upticks in free-trial sign-ups, aside from the initial launch, have corresponded with the premiere of new originals, and more than 7 million comics have been read on the service.

The platform has so far been directed at a specific fanbase, but experts say attracting casual viewers and exclusive content will be key to its longevity.

When DC and Warner Bros.' DC Universe streaming service launched in September, it labeled itself as the "ultimate DC membership" for fans, a place where the DC fandom could watch their favorite movies, read their favorite comics, and gain access to exclusive original content for $7.99 a month.

That focus was in contrast to prominent streaming services such as Netflix, which has nearly 140 million subscribers worldwide and appeals to wide range of audiences. And DC Universe launched into an uncertain market for niche streaming services, some of which have shut down in recent years, including the classic-film service FilmStruck, the Korean drama service DramaFever, and the comedy-centric Seeso.

Five months later, has DC Universe proved it's here to stay? Experts say the momentum is there, but it will have to evolve like any other streamer.

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On the originals front, the service has hit the ground running. A spokesperson told Business Insider that the biggest upticks in free-trial sign-ups, aside from the initial launch, have corresponded with the premiere of new series. DC Universe's first two original programs, the live-action "Titans" and the animated "Young Justice: Outsiders," have consistently been among the seven most in-demand streaming shows in the world, according to weekly data provided to Business Insider by Parrot Analytics.

The shows have been praised by critics, too. "Titans" has an 84% Rotten Tomatoes score, and the new season of "Young Justice" has a 91%. The latest series to debut on the service, "Doom Patrol," is sitting at 93%.

Unlike Netflix, which drops entire seasons at once, DC Universe releases episodes on a weekly basis. "Doom Patrol" showrunner Jeremy Carver said this gives the service an advantage in sustaining buzz with only a few originals out.

"I love to binge as much as the next person, but there is something exciting about rolling it out," he told Business Insider. "All of these episodes are unique from one another. And, I think, particularly when you pair that with launching a new service, the hope is that you're building momentum with each and every episode and folks are talking about it, and other folks want to be part of that."

By the end of January, the DC Universe mobile app had passed 1 million installations on the App Store and Google Play, and revenue was up 53% in January compared with December, according to data from the mobile-marketing-insights company Sensor Tower provided to Business Insider (this is for only the mobile app and doesn't include other platforms such as desktop and Roku).

Sensor Tower cofounder Alex Malafeev told Business Insider the mobile app's revenue growth "paints a positive picture for the service when looked at in comparison to other niche subscription offerings on mobile which have grown more modestly in their first several months of availability."

"Titans." DC Universe

How DC Universe can survive for years to come

Jim Lee, DC's chief creative officer, told Business Insider in August ahead of the DC Universe's launch that it wasn't trying to compete with Netflix. Lee said DC Universe was "not an attempt to be everything to everyone," but rather "an attempt to be the most immersive experience for fans of the DC characters and stories."

Malafeev said DC Universe will have to keep delivering original content that "resonates as strongly with its target audience" if it wants to continue its success.

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Upcoming DC Universe originals in 2019 include "Swamp Thing" and an animated "Harley Quinn" series. It also doubled the number of digital comics available to read in February, and a spokesperson said more than 7 million comics have been read since launch. It also recently made the animated movie "Reign of the Supermen" available to stream on the same day it was released on Blu-ray.

But it can't just appeal to its loyal users. Brice Clinton, a senior engineer at CSG with expertise in streaming services, said attracting casual users will be essential. He said the service should leverage hit movies, such as "Wonder Woman" and "Aquaman," to its advantage and stream them exclusively (the service includes classic "Superman" and "Batman" movies).

"It doesn't need Netflix numbers," Clinton told Business Insider. "Think about it like sports. With football, there's always the rabid fan. But the NFL is really trying to attract the casual fan because the hardcore fan is always going to be there anyway. Does it need to have mass appeal? No. But to attract the casual fan, I think that's important for them. It's always going to have that ingrained base, but can it get one other set of people?"

"I always hope that we can bring more people in with a story that’s even more universal than just superheroes," "Doom Patrol's" Carver said about bringing in casual viewers. "But I say that with a certain amount of naivety because I think superhero stories are relatively universal."

Have a tip about DC Universe or anything else? Email the author at tclark@businessinsider.com.