At /e/ we had lots of discussion about Telegram vs Signal vs ... But I must say that the best IM secured service in my opinion is @firstname.lastname@example.org
Delta Chat is using emails to transport instant messages: it's fully decentralized, heavily encrypted and you can reach any contact
chaos.social - because anarchy is much more fun with friends.
chaos.social is a small Mastodon instance for and by the Chaos community surrounding the Chaos Computer Club. We provide a small community space - Be excellent to each other, and have a look at what that means around here.
Follow @ordnung for low-traffic instance-related updates.
The primary instance languages are German and English.