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. Although some channels have been removed, the curation process is considered opaque and insufficient by analysts. The gold standard of encryption, known as end-to-end encryption, where only the sender and person who receives the message are able to see it, is available on Telegram only when the Secret Chat function is enabled. Voice and video calls are also completely encrypted. "There is a significant risk of insider threat or hacking of Telegram systems that could expose all of these chats to the Russian government," said Eva Galperin with the Electronic Frontier Foundation, which has called for Telegram to improve its privacy practices. He floated the idea of restricting the use of Telegram in Ukraine and Russia, a suggestion that was met with fierce opposition from users. Shortly after, Durov backed off the idea.
from ru