[room505]

My family has been using Threema, which doesn't require a phone number.

[cmeacham98]

Proprietary? No thanks. Even Signal open-sources their client.

[room505]

I'm not sure what is proprietary...https://threema.ch/en/open-source

[cmeacham98]

Oops ... :/

I can't edit my comment to correct it now, but in my defense Wikipedia says it's proprietary

[Grumbledour]

https://github.com/orgs/threema-ch