Keeping your chats secureMarkus Ra
Telegram encryption protects your messages when they travel along the communication lines and when they rest in Telegram's encrypted cloud. Secret Chats are further protected by a layer of end-to-end encryption, and cloud chats – by Telegram's distributed cross-jurisdictional infrastructure.
In the 6 years of its existence, Telegram shared 0 bytes of data with third parties. China, Iran and Russia are currently blocking the app because they couldn't access user data.
Here are some tips on how to further secure your account and your data:
2-Step Verification: Cloud password
By default, you can use an SMS code to your phone number to log in to Telegram on a new device and access your cloud chats. This is an industry standard for logging into messaging apps. However, if you have reasons not to trust your mobile carrier or your government, or would simply like more control, we advise protecting your cloud chats with an additional password.
To do that, go to Settings > Privacy & Security > 2-Step Verification and choose a strong password (here's one way to come up with one).
If you want to make sure that some messages are not a part of your multi-device chat history on Telegram, you can try Secret Chats. They use end-to-end encryption so that the messages in them can be accessed only from the two participating devices. Even if I manage to intercept your SMS code, steal your password and log in to your account, I won't see your Secret Chats.
You can also enable a self-destruct timer for Secret Chats. Once viewed, messages will disappear on both ends after the time runs out.
Remember that in every scenario, your device is the ultimate guardian of your data. No messaging app can protect you against people who have access to your device.
To protect your device from malware, keep your operating system updated to the latest version and never install apps from suspicious sources. It is also advisable to only use official Telegram apps.