I had suggested Wire [1] in a comment above [2]. It's cross platform, has cross device sync, and end-to-end encryption. Sign up can be using the phone number or

I had suggested Wire [1] in a comment above [2]. It's cross platform, has cross device sync, and end-to-end encryption. Sign up can be using the phone number or an email address. [1]: https://www.wire.com https://www.wire.com [2]: https://news.ycombinator.com/item?id=12296477 https://news.ycombinator.com/item?id=12296477