Wickr vs Signal
Signal has always been a reliable messenger, and is regularly updated with big fixes, performance improvements and tweaks. It’s most recent update has given it a massive yet subtle facelift that now has the look and feel of a modern app, a great improvement over the previously dated (although functional and consistent) interface.
More information: https://www.signal.org/fr/
Wickr is above all military and intelligence community standards for top-secret communications is now the default communication and collaboration platform for the US Department of Defense, many other agencies and many Fortune 100 companies.
This app was seen in the Mr Robot series, and allows group discussions up to 10 people. Messages can be deleted automatically after a lapse of time ranging from 3 seconds to 6 days. The conversations are encrypted.
More info: https://wickr.com/me/
The main obstacle to wickr is that there are few users on it, a bit like Signal before the 2020s. Too bad, because we like Wickr better since no phone number is required to register.