In a new report from consumer research company Nielsen, Facebook's (NASDAQ:FB) dominance stands out in a list of 2016's most popular mobile apps in the U.S. But the list also highlights some key takeaways about Alphabet (NASDAQ:GOOG) (NASDAQ:GOOGL), (NASDAQ:AMZN), and Apple (NASDAQ:AAPL). Here's a look at the Nielsen's top 10 apps of 2016, along with four observations.

Image source: Getty Images.

  1. Facebook
  2. Facebook Messenger
  3. YouTube
  4. Google Maps
  5. Google Search
  6. Google Play
  7. Gmail
  8. Instagram
  9. Apple Music
  10. Amazon App

Facebook is crushing it

In line with Facebook's recent impressive global growth in monthly active users, the world's largest social network's user base continued to grow handsomely in the company's home U.S. market. Facebook's average monthly active users (MAUs) in the U.S. during 2016 increased 14%, according to Nielsen.

Facebook's Messenger also performed exceptionally, raking in 28% year-over-year growth and coming in second only to Facebook's own native app. Messenger's success follows a year of big investments in the messaging app, including live video, messaging bots, and business integrations. Messenger's 28% growth in U.S. MAUs doesn't necessarily come as a surprise, considering Facebook's global Messenger MAUs increased from 700 million in the third quarter of 2015 to over 1 billion by July. 

Instagram. Image source: Instagram.

And Facebook's Instagram was a smash hit in 2016, too. Coming in at number eight on Nielsen's list, the photo- and video-sharing app saw its U.S. MAUs increase 36%.

Further, not only was Facebook's growth notable, but both Facebook and Messenger's 146 million MAUs and 130 million MAUs, respectively, were still well ahead of third-place YouTube's 114 million MAUs.

Alphabet is succeeding on numerous fronts

Google parent company Alphabet continues to shine in terms of the quantity of Google-branded apps making it into Nielsen's top 10, highlighting Alphabet's robust ecosystem of apps for simultaneously serving its customers and generating data for its advertisers. Alphabet's YouTube, Google Maps, Google Search, Google Play, and Gmail all made Nielsen's top-10 list.

Apple Music remains a key player in streaming music

While streaming music company Spotify continues to outperform Apple Music when it comes to paying members across the globe, Apple Music is winning in the U.S. when it comes to unique monthly visitors to the streaming music app. In a nod to the continued success of Apple's streaming music service, Apple Music was number nine on Nielsen's list, clocking a notable 20% year-over-year uptick in monthly active users. Spotify didn't make the list.

This data reflects recent updates about Apple Music from the tech giant. The streaming service's paying subscribers recently surpassed 20 million, Apple said earlier this month. This is up considerably from 10 million in January. 

Amazon mobile app. Image source: Amazon.

Amazon's soaring growth puts it in the top 10

Thanks to its monstrous 43% growth in monthly active users, Amazon's shopping app made a surprising entrance to Nielsen's top-10 list this year. The app's inclusion in Nielsen's top 10 apps shows how successfully the company has been riding the e-commerce wave in the wake of rising mobile adoption.

Amazon's own data about global usage of its shopping app during the peak holiday season points to a similar trend. Shopping on the company's free mobile Amazon app increased by 56% during this important period, according to an update from the company this week. 

These observations reinforce how Facebook, Alphabet, Apple, and Amazon consistently earn customer attention.

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