[multjoy]

Encrochat is a funny example - WhatsApp and Signal were widely available at the time and were entirely secure.

Encro was a home-brewed system that pretended to be more than it was while the target market would have been much better off with an up-to-date stock android or iPhone handset + Signal and basic security awareness. The vulnerability around the handset is certainly significantly less than whatever cobbled together android distro they were using, and if the messages are on the handset then they are always vulnerable to recovery.