Giving a unique snapshot into who is using what platform in the fast-emerging yet hotly competitive vMVPD market, research company Apptopia said that usage of the DirecTV Now mobile app increased by 185% year over year in March.

Apptopia, which supplies mobile app makers with data on their products, also found that year-over-year usage of fuboTV and Hulu apps increased by 170% and 163%, respectively.

Conversely, usage of the Sling TV mobile app fell 34%, Apptopia found.

RELATED: Sling TV signups are slowing down, on track to be overtaken by DirecTV Now, research firm says

The findings dovetail with a Strategy Analytics report released last week that suggested Sling TV subscriber growth had fallen behind that of DirecTV Now, with the latter picking up 1 million users in 2017 while the former added 700,000.

"We are asserting that usage for Sling TV's mobile app is down YOY,” said Adam Blacker, communications lead for Apptopia, in an email to Fierce this morning.

In the chart supplied by Apptopia above, the company didn’t include data for YouTube TV, which didn’t launch until early April of last year.

Blacker noted, however, “In its first month, we estimated the app to have 138,000 unique users, and today we see the app has grown to about one million monthly active users. There have been reports of YouTube TV having about 300,000 subscribers. Just like a Netflix login, people in households and maybe even some ex-girlfriends are sharing a login."

Blacker’s report also excluded Sony’s PlayStation Vue, “because while it fluctuates, it has essentially not grown or diminished its MAU.”

Notably, Apptopia also found that Hulu generated $37.6 million in in-app purchases during the first quarter, making first-quarter 2018 its most lucrative quarter ever. In fact, that IAP revenue figure was bigger than the last two quarters combined for Hulu.

For his part, Blacker tied the growth to Hulu’s promotional push.

“Earlier this month, Hulu struck a deal with the National Hockey League to become the official sponsor of the NHL’s Stanley Cup Playoffs,” he wrote. “As I watch my Boston Bruins on YouTube TV, I do feel weird about seeing all those Hulu logos everywhere. But Hulu’s ad blitz has been paying off if we look at the explosion of growth it has experienced over the past year.”