2021 had its share of unconventional moments, but mobile apps continued to be reliable tools for work, entertainment, communication and shopping. While people spent leisure time using TV streaming services like Netflix or scrolling through social media sites such as Instagram, they also stayed connected with Zoom and Facebook. But TikTok solidified itself as the most popular app of the year.

Apptopia compiled its list of the most downloaded apps of 2021, and the video-sharing app grabbed the top spot among global users. Apptopia gleans data from mobile app stores to examine which areas have the most growth and which brands raked in the highest number of downloads. Analyzing information from Google Play and iOS' App Store, the company determined the top 10 mobile apps in the U.S. and the world. ByteDance-owned TikTok sits in first place on both charts.

According to Apptopia's global list, TikTok had 656 million downloads in 2021. It's followed by Instagram (545 million), Facebook (416 million), WhatsApp (395 million), Telegram (329 million), Snapchat (327 million), Zoom (300 million), Messenger (268 million), CapCut (255 million) and Spotify (203 million). It's noted that ByteDance is also the parent company for CapCut, a free video editing app that enables users to create and edit clips -- which can then be exported to TikTok.

In the U.S., TikTok's 94 million downloads outranked Instagram's 64 million. But the rest of the country's top 10 include Snapchat (56 million), Cash App (56 million), Zoom (52 million), Messenger (51 million), Facebook (47.3 million), WhatsApp (47.2 million), YouTube (47 million), and HBO Max (45 million). Domestically, HBO Max beat its TV streaming competitors and bumped Netflix to No. 2.

Compared to Apptopia's 2020 findings, TikTok still ranked No. 1 but experienced a higher download volume last year globally. But 2021 saw the video app's U.S. downloads increase by 6 million. If you're looking to get in on the wave, check out CNET's handy guide to joining TikTok. 

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