In the case of TikTok, 15-second dance clips and memes dominate the platform, although some videos do show youngsters, some scantily clad, lip-syncing and grooving to popular tunes. Local media have also reported several accidental deaths when users attempted to make videos with knives and guns.
The IT minister of Tamil Nadu state, M. Manikandan, said in February that "young girls and everybody is behaving very badly" on TikTok.
On Wednesday, TikTok vanished from Google and Apple's app stores in India. The rare takedown of such a popular app came after the Madras High Court said the app encouraged pornography and asked the government to ban it. The federal IT ministry then issued a follow-up directive to Google and Apple.
Industry executives, technology lawyers and free-speech activists interviewed by Reuters on Wednesday said the ban was a major concern.
"It does unnerve me," said a senior executive working for a social media company in New Delhi. "For the industry, it sets a worrying precedent in India."
A TikTok spokesman said on Wednesday that it had faith in the judicial system and was "optimistic about an outcome that would be well received by" its millions of users in India. The state court will next hear the case on April 24.
Google told Reuters late on Tuesday it does not comment on individual apps but adheres to local laws. Apple did not respond to requests for comment.
TikTok is not the first social media company to run into trouble in India.
Facebook FB.O and its messenger app WhatsApp, which count India as their biggest market, have been under pressure from authorities to better tackle fake news and monitor content on their platforms.
Global video streaming giant Netflix was dragged into a legal battle last year following a complaint that one of its fictional series insulted a former Indian prime minister.
But industry executives said the ruling against TikTok was particularly worrisome, given that it originated from a public interest complaint brought by an individual in Tamil Nadu - opening their digital content to judicial scrutiny that could potentially derail their India strategy overnight.
"It shows a level of uncertainty which is not great for investors, for private equity firms and for venture capital," said Apar Gupta, executive director at advocacy group Internet Freedom Foundation.
India is a critical market for social media and mobile digital content companies as the country is witnessing a sharp surge in use of smartphones. An estimated half-a-billion Indians now have access to the Internet.
Singapore-based Bigo, which has a live video streaming app, has also been expanding in India. TikTok's owner Bytedance Technology Co, one of the world's most valuable start-ups, also runs another social app named Helo, which allows users to share content in local languages.
Bytedance has more than 250 employees in India, with plans to expand further, one of its court filings showed. It had about two dozen India job openings listed on LinkedIn as of Wednesday.
Such is the TikTok craze that a Reuters photographer recently saw more than a dozen youngsters shooting TikTok videos on their smartphones at a popular Mumbai promenade. While some danced as they lip-synced to songs, others used teddy bears as props.
The Tamil Nadu court, which ruled against TikTok, said inappropriate content was its dangerous aspect and that the app could expose children to sexual predators.
The ban does not apply to use of the TikTok app if it has already been downloaded.
The Chinese company unsuccessfully argued at the Supreme Court last week that a ban "amounts to curtailing of the (free speech) rights of the citizens of India".
A "very minuscule" proportion of TikTok's videos were considered inappropriate or obscene, the company said in its Supreme Court filing, adding that it was primarily an entertainment platform.
That argument cut no ice with the app's critics, however.
Hindu nationalist group Swadeshi Jagaran Manch, which is close to India's ruling party and had previously criticised the app's content, on Wednesday welcomed the ban, saying TikTok was "against Indian culture and morality".
It also struck a chord in some family living rooms in India.
"From small kids to old ladies, it is spoiling the minds of everyone," said S. Nithyajothi, a homemaker from the southern city of Madurai. "I strictly ask anyone coming to my house to not talk about TikTok, it is addictive and it is unnecessary."
(Reporting by Aditya Kalra and Sankalp Phartiyal; Additional reporting by Sudarshan Varadhan and Danish Siddique; Editing by Martin Howell and Alex Richardson) ((firstname.lastname@example.org; +91-011-49548021; Reuters Messaging: email@example.com (Twitter: @adityakalra))