Individual messages can be fully encrypted. But the user has to turn on that function. It's not automatic, as it is on Signal and WhatsApp. "And that set off kind of a battle royale for control of the platform that Durov eventually lost," said Nathalie Maréchal of the Washington advocacy group Ranking Digital Rights. Some privacy experts say Telegram is not secure enough The Security Service of Ukraine said in a tweet that it was able to effectively target Russian convoys near Kyiv because of messages sent to an official Telegram bot account called "STOP Russian War." Telegram boasts 500 million users, who share information individually and in groups in relative security. But Telegram's use as a one-way broadcast channel — which followers can join but not reply to — means content from inauthentic accounts can easily reach large, captive and eager audiences.
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