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. You may recall that, back when Facebook started changing WhatsApp’s terms of service, a number of news outlets reported on, and even recommended, switching to Telegram. Pavel Durov even said that users should delete WhatsApp “unless you are cool with all of your photos and messages becoming public one day.” But Telegram can’t be described as a more-secure version of WhatsApp. In the United States, Telegram's lower public profile has helped it mostly avoid high level scrutiny from Congress, but it has not gone unnoticed. As a result, the pandemic saw many newcomers to Telegram, including prominent anti-vaccine activists who used the app's hands-off approach to share false information on shots, a study from the Institute for Strategic Dialogue shows. But Telegram says people want to keep their chat history when they get a new phone, and they like having a data backup that will sync their chats across multiple devices. And that is why they let people choose whether they want their messages to be encrypted or not. When not turned on, though, chats are stored on Telegram's services, which are scattered throughout the world. But it has "disclosed 0 bytes of user data to third parties, including governments," Telegram states on its website.
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