Jami uses git and TLS to implement E2E encrypted chats.[1] That doesn't sound all that secure to me. I'd feel much more comfortable using a fork of Signal with an onion router.

I don't get the prejudice some have against blockchains either. It's not even like this is Keybase where they shoehorned a crypto wallet into the app. They do have a wallet but it's a totally separate application. Session is purely a messenger and nothing else, you'd have no idea a blockchain was involved at any part of the backend if you weren't told about it.

I have played around with Tox and it's a cool project, but it's been in beta since 2014 and is not well optimised for mobile at all. I don't think it'll go very far personally.

[1] https://jami.net/swarm-introducing-a-new-generation-of-group...