The short-video app TikTok has seen its billionth download on the Apple App Store and Google Play Store combined. It has also rivalled Facebook and surpassed Instagram for app install counts in 2018. It was also the most-downloaded non-game app in the US in January 2019.
https://www.notebookcheck.net/TikTok-has-amassed-over-a-billion-downloads-on-iOS-and-Android.411538.0.html