It's only been about two months since Disney (NYSE:DIS) launched Disney+, its biggest push into subscription video on demand (SVOD) services. There have already been mounting signs that the service is enjoying incredible demand, as indicated by website outages caused by excessive traffic, soaring popularity of The Child ("Baby Yoda") from The Mandalorian, grabbing 10 million sign-ups on the first day, and booming search queries.

Here's even more evidence that Disney+ is a massive hit.

The Child sucking on a pendant

Image source: Disney.

Disney+'s launch was "unprecedented"

This week, mobile analytics specialist Sensor Tower released its latest report on mobile apps in Q4, which shows that Disney+ became the top downloaded app in the U.S. despite launching about halfway through the quarter.

The debut was the "biggest story of Q4 2019" and "unprecedented," according to Sensor Tower, grabbing an estimated 31 million downloads in the U.S. That was more than double the No. 2 downloaded app, TikTok. The data only includes mobile platforms (iOS and Android) and does not cover subscribers that may access the service on desktop browsers or other platforms (like smart TVs).

Disney+'s launch on Nov. 12 helped expand the broader SVOD market, and Disney grossed over $50 million in the first 30 days. "In December, Disney+ earned more revenue in the U.S. than HBO NOW's best month," according to Sensor Tower. "This includes the revenue spikes HBO NOW saw alongside the release of the final season of Game of Thrones."

That's an incredible accomplishment given the massive popularity of AT&T's (NYSE:T) dragon show. HBO NOW's peak revenue month was back in August 2017, when it released the seventh season of Game of Thrones, and Disney+ topped that with between $35 million and $40 million in revenue in December. (The aforementioned $50 million figure includes only half of December.) Keep in mind that these estimates don't include customers that subscribe to HBO through cable operators.

Disney+ represented a 34% share of all SVOD app downloads in the fourth quarter, topping the downloads that competing services Amazon Prime Video and Hulu had throughout the entire year. Disney owns most of Hulu and has operational control of the company, and a bundle including Disney+, Hulu, and ESPN+ is helping to boost Hulu downloads.

Market leader Netflix (NASDAQ:NFLX) has seen its share of mobile U.S. SVOD revenue decline from 32% in Q1 to 15% in Q4, although that's partially a function of the video-streaming company's decision to stop selling in-app subscriptions. That's caused a meaningful decline in mobile revenue, although Netflix still brings in some mobile revenue from existing subscribers that had previously signed up through those platforms.

Sensor Tower believes that Netflix would have grown mobile revenue throughout 2019 if it still offered in-app subscriptions, although the company would have to hand over a cut. Avoiding that hefty tax is the whole reason Netflix is trying to nudge people to sign up directly online.

With Disney+ putting up numbers like this, hitting those lofty subscriber goals might be a piece of cake.