Fifteen-second videos and an endless stream of music; this, in a nutshell, is what the TikTok app promises its users. You may have heard of it. You may even have downloaded it and probably deleted it quickly because the amount of bizarre content was too terrifying. That's alright, Some 40 percent of the app's users are under the age of 24.

TikTok is a social media app for "vertical video" streaming powered by artificial intelligence (AI). Once you've downloaded it and even before signing up, you already receive short videos in your feed. Content is sampled automatically and mainly features videos of of people dancing, singing, lip syncing and performing all sorts of stunts.

On average, users spend 52 minutes a day using the app, which adds up to roughly 200 videos per day. TikTok is structured around a never-ending video feed. Unlike your friend's feed on Facebook or a follower's feed on Twitter, the stream is generated by an AI algorithm jumping on trending topics and ultimately your preferences.

It also invites users to interact with already produced content using the unique feature of duets — videos that are filmed to go with existing clips using the same soundtrack — and by participating in trending challenges.

Who is on TikTok?

According to the most recent data available, TikTok had 500 million active monthly users in June 2018. Still a far cry from Instagram's 1 billion and Facebook's 2 billion active users. But in September, the Chinese app beat Facebook, Instagram, Youtube and Snapchat in terms of daily downloads.  

Most TikTok users are young. About 41 percent are between 16 and 24 years old — more or less the same age as many of the so-called influencers active on the service. Two German teens from Stuttgart, Lisa and Lena, both 16, are the superstar acts with a following of 31.5 million followers.

Among young people TikTok has become an app which they use when bored. "It is easily one of the funniest and most addictive apps you can ever get," a user named Matt Burns comments on Google Play. 

ByteDance fortunes soar

TikTok is the brainchild of Chinese tech startup ByteDance. The Beijing-based company was founded in 2012 and develops mobile-first applications based on machine-learning. Outside of China, the company is primarily known for its TikTok app, but its actual flagship product is Jinri Toutiao — meaning "headlines from China". The app is capable of tracking users' reading habits, and has several offspring created for different markets such as Helo, available in 14 Indian regional languages, and TopBuzz for English readers.

In 2016, ByteDance launched a short-video app called Douyin, intended for the Chinese market. Within just one year, it had been downloaded by 100 million users and became the precursor to the TikTok app for international users launched in September 2017.

ByteDance has since expanded rapidly by buying Shanghai-based video app Musical.ly for $1 billion (€890 million) in December 2017, and merging two other startups to create the TikTok brand in August 2018. As TikTok is said to have become the largest video community platform in the world, US-based social media platforms are increasingly nervous about their market share. In November, Facebook for example quietly launched its own short-video app called Lasso and aimed to counter the meteoric rise of TikTok.

The Chinese success has meanwhile moved ByteDance into the limelight of investors' attention. In October 2018, the company secured funding to the tune of $3 billion from the Japanese SoftBank Group and other major investors. This has caused its market value to soar to $75 billion, surpassing that of Uber and making ByteDance the world's most valuable privately-backed startup. 

Safety concerns  

However, TikTok's rise has been overshadowed by a series of security issues and data  scandals. In February, the US Federal Trade Commission fined the company $5.7 million for breaching child privacy laws after it had become known that TikTok collected names, email addresses and other data from children younger than 13 years without parental consent.

Naman Aggarwal, Asia Policy associate at digital rights advocacy group Access Now, says TikTok's rights violations go well beyond the United States.

"It becomes even more concerning because in certain jurisdictions that don't have an adequate data protection framework, there aren't enough safeguards when it comes to children," he told DW. He wants the company to make sure its consent guidelines are applied irrespective of the country they operate in. In addition, he fears the platform might even "incentivize" children to share "sexually explicit content."

"This is a more complex problem, because determining if particular content violates the company's community guidelines could be tricky and might have an impact on the freedom of expression of users," Aggarwal says, adding that TikTok accounts are by default public, allowing even non-registered users to get access to such dubious content.

Aggarwal stresses that TikTok and other platforms should be held responsible for "ensuring that they protect the rights of the users and provide a safe environment for them," especially when so many children and teenagers use it.

But TikTok seems to apply international standards more lightly than others. In July 2018, it was banned in Indonesia for featuring content deemed pornographic and blasphemous. The ban was lifted after a week, though, because TikTok agreed to clear negative content and hired a local moderator in the country.

Aggrawal believes that "regional moderators" could be a major step foward in preventing such violations, but adds "it should also be ensured that they do not sacrifice users' freedom of expression on the platform itself."