The Best Encrypted Messaging Apps You Can (and Should) Use Today
heimdalsecurity.com
heimdalsecurity.com
It also misses community-based projects like Tox, Ring that are end-to-end encrypted and decentralized (DHT) by design and Riot (federalised Slack-like with end-to-end encryption), or Wire - one of the most feature-complete IMs.
I did get a confirmation from Wire.com's support this morning that they are aware of the problem. Seems fixed now.
Many of these services are unauditable and should not be used for secure communications. Security is opt-in in cases, and there are even warnings in the article that certain things are not end-to-end encrypted.