• by Gavin O'Malley , Staff Writer @mp_gavin, December 21, 2015

So far, Facebook’s app diversification strategy is working better than anyone could have predicted.

Over the past year, in fact, Facebook Messenger grew faster than any other app, according to fresh findings from Nielsen. All told, the standalone app saw a 31% increase in users.

Despite mixed reviews, Apple Music was the second-fastest-growing app of the year -- with 26% growth since the end of 2014.

Overall, Facebook’s flagship app remained the most downloaded among U.S. smartphone users, Nielsen found. The social giant boasted more than 126 million average unique users each month, which represented a growth of 8% year-over-year.

YouTube, meanwhile, came in second with over 97 million average unique users each month, followed by Facebook Messenger with more than 96 million average unique users each month.

By comScore’s count, Facebook Messenger actually surpassed YouTube’s app in terms of consumer reach this year.

Regardless, it’s now clear that Facebook’s controversial decision to separate Messenger from its core app is paying off.

Now the question is, how many Facebook-controlled apps will consumers be willing to hold on their phones?

The question is particularly salient as the social giant is about to require users to download a separate Moments app in order to sync their mobile pictures. The change -- which will mean no more syncing on Facebook’s flagship app -- will reportedly go into effect in early January.

Since its debut in 2012, auto-syncing has enabled mobile users to store their snaps in Facebook albums. Launched this past summer, Facebook’s Moments app automatically creates albums of users and their friends with the help of proprietary face-recognition technology.