Downloads fell by more than 2 million between 5-12 January compared to the previous week, shrinking to 10.6 million.
This is now less than both Signal and Telegram, which saw 17.8 million and 15.7 million downloads respectively during the same time period, data from app analytics firm Sensor Tower revealed.
The dwindling demand for the Facebook-owned app follows widespread dissatisfaction with how it treats user data.
Users outside of the UK and Europe will now be subject to a data-sharing agreement between WhatsApp and Facebook, which will see private details like phone number, IP address and browser information.
The exodus has panicked WhatsApp, who took out full-page adverts in India’s newspapers this week asking users not to leave.
“WhatsApp respects and protects your privacy,” stated the message, which appeared on the front page of The Indian Express and The Hindu, as well as in eight other newspapers.
“WhatsApp cannot see your private messages or hear your calls, and neither can Facebook: Every private message, photo, video, voice message, and document you send to your friends, family, and co-workers in one-on-one or group chats is protected by end-to-end encryption. It stays between you.”
A significant number of conservative users have have also deserted the platform after Facebook joined all other major social media platforms in banning Donald Trump and his most extreme followers from their platforms.
The massive influx of new users to Telegram led the app’s founder to describe it as “the largest digital migration in human history".
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