https://techcrunch.com/2020/04/24/telegram-hits-400-million-monthly-active-users/

Instant messaging service Telegram has amassed 400 million monthly active users, it said today, up from 300 million active users the seven-year-old service disclosed to the SEC last October.

The service — founded by Pavel Durov, who also created Russian social networking site VK — said it adds about 1.5 million users each day and is the most downloaded social media app in over 20 nations.