Telegram

Telegram is a messaging app built around large groups and broadcast channels, with a bot platform that makes it a common backend for notifications, alerts and small automated services.

Groups scale to hundreds of thousands of members and channels broadcast one-way to unlimited subscribers, which is why it dominates in crypto, trading and technical communities where an announcement needs to reach everyone at once.

On security: regular chats are encrypted in transit but stored on Telegram's servers, and only Secret Chats are end-to-end encrypted. If confidentiality is the requirement, that distinction matters.