Update March 8, 2022: EFF has clarified that Channels and Groups are not fully encrypted, end-to-end, updated our post to link to Telegram’s FAQ for Cloud and Secret chats, updated to clarify that auto-delete is available for group and channel admins, and added some additional links. I want a secure messaging app, should I use Telegram? In addition, Telegram's architecture limits the ability to slow the spread of false information: the lack of a central public feed, and the fact that comments are easily disabled in channels, reduce the space for public pushback. In the past, it was noticed that through bulk SMSes, investors were induced to invest in or purchase the stocks of certain listed companies. Telegram does offer end-to-end encrypted communications through Secret Chats, but this is not the default setting. Standard conversations use the MTProto method, enabling server-client encryption but with them stored on the server for ease-of-access. This makes using Telegram across multiple devices simple, but also means that the regular Telegram chats you’re having with folks are not as secure as you may believe.
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