If you've ever been in an abusive relationship, it tunes you for picking up on the signals that indicate that others are, too. When someone puts themselves in a position of unequal power or control over another person or group, they follow many of the same behaviours, because their actions come from a place of fear.
They fear to lose control of the situation they've created, they fear that the other person will reach out to potential allies, and they fear that - in spite of all of their efforts - the victim they are trying to manipulate will get information that allows them to break away from their web of control.
Telegram is a great, popular app. It's used by a lot of people. It has been used quite a bit to quickly organise groups and to share information. This has allowed it to attract quite a bit of attention from the wrong types of people.
However, Telegram is not secure. It uses a very simple in-house security that has been breached by individuals and governments both through social engineering (where someone basically poses as a friend to gain the confidence of others) and through the messaging data that it sends "in the clear."
As good as it is, I can't recommend that people use Telegram for their business or even private conversations. Instead, they should use Signal.
No, this is not an advertisement for Signal. In fact, they're a non-profit group that believe in the power of open source. It's not perfect - nothing is - but their service is far more savvy than many others.
Signal messages - when used by two people using the app - are encrypted at both ends. So even if someone is sifting through your data, they won't be able to understand what it says. It also has biometric and other security challenges that make it difficult for people to just open your phone and read your messages.
As someone who has had their phone sifted through at leisure because I trusted someone else close to me, I can assure you that even the most benign messages and information can be used against you. The kind of people who want absolute control over you will find a way to make it mean what they want it to mean.
If you care about keeping your business details secure, or you or someone you know has been in an abusive relationship, you know how important keeping information private is. Signal is recommended by some pretty powerful people. Both Edward Snowden and the US military use it, so that should tell you something!
Go check it out for yourself https://signal.org/install
To add me, you can use this number +86 133 1894 6421
Don't bother calling; I blacklist all calls on this number. It's only used for adding me as a contact.