India is WhatsApp's largest market, and with more than 500 million users, it enjoys a far bigger user base here than Telegram.

After sending a notice to WhatsApp, the IT Ministry has now sent a notice to Telegram and Signal, raising questions on their existing username feature and asking how the platforms are addressing concerns related to fraud and impersonation, according to a source.
Sources said that in the notice to Telegram, the government has asked the platform why it should be allowed to retain the username feature.
On Wednesday, the Centre issued a notice to Meta over the username feature on WhatsApp, citing concerns that it could materially increase online fraud, phishing, digital arrest scams, and impersonation attacks.
It had also directed WhatsApp to pause the feature until consultations on the issue are completed "to the satisfaction of the Government".
The government has now widened its scrutiny to other messaging platforms as well, sources said.
Sources told PTI that the IT ministry has also written to Telegram and Signal - which already have the username feature - and asked how concerns around fraud and impersonation are being addressed by them.
In its notice to WhatsApp, the government had expressed concern that the proposed username feature may "materially increase" cases of online fraud, phishing, digital arrest scams, and impersonation attacks by enabling bad actors to solicit and message victims.
Meta was asked to explain why action shouldn't be initiated under the IT Act and rules over WhatsApp's new feature that may increase cybercrimes.
The Centre also reminded Meta that WhatsApp, as a significant social media intermediary, was bound by due diligence obligations under the IT Act and rules.
WhatsApp, in a statement on Wednesday, defended the feature, citing built-in safeguards to prevent scams and impersonations and protect users.
India is WhatsApp's largest market, and with more than 500 million users, it enjoys a far bigger user base here than Telegram.
Over the past month, Telegram came under the regulatory lens in India over concerns related to fraud, impersonation and circulation of sensitive content. The Indian government had imposed a ban on Telegram and its associated web services until June 22, citing the platform's failure to curb the circulation of leaked and fake National Eligibility-cum-Entrance Test (NEET) examination papers, misleading content and other fraudulent activities linked to the country's medical entrance examination process. The Instant messaging platform, however, returned to service in India after a week-long government ban expired.
(Except for the headline, Fortune India has not edited the content of this PTI report.)