Sensor Tower added that the billion figure did not include Android installs from China, so the real number of installs is likely to be much higher.
Roughly 663 million of TikTok's total one billion downloads came in 2018, meaning it was downloaded more last year than Instagram, which garnered 444 million new downloads.
Popular with children and pre-teens, Sensor Tower's data shows that TikTok seems to be taking off in the Indian market. In January 2019, 43% of the apps new users were from India, up from 9.5% in January 2018.
TikTok started life as two separate apps, named TikTok and Musical.ly. Chinese tech company Bytedance bought lipsyncing app Musical.ly for $1 billion in 2017, and announced in August 2018 that it was scrubbing the Musical.ly name and merging it with its own app TikTok. Since then it has evolved into a short-form video app which has been likened to the now-defunct Vine.
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