Slack isn&#x27;t encrypted and it doesn&#x27;t make sense to pretend that it is. Introducing encryption is actually difficult for them, since they rely on a web interface connecting to a central server.<p>But anyway, email can support encryption if you want it, not by one, but two protocols. Email is actually the main channel that journalists and businesses are using for communicating actual secrets over the wire. It&#x27;s actually the only generally available &quot;<i>meaningful</i>&quot; channel, because even with WhatsApp&#x27;s encryption, you still can&#x27;t fully trust a binary blob communicating with a proprietary server, not without the ability to do third-party reviews.<p>You can do  S&#x2F;MIME, which is encryption with certificates released by an authority (just like HTTPS), or you can do PGP&#x2F;GPG which is more decentralized, putting the onus of establishing a chain of trust on you. S&#x2F;MIME is supported out of the box in most email clients and setting up GPG in something like Thunderbird is actually not that hard: <a href="https:&#x2F;&#x2F;support.mozilla.org&#x2F;en-US&#x2F;kb&#x2F;digitally-signing-and-encrypting-messages" rel="nofollow">https:&#x2F;&#x2F;support.mozilla.org&#x2F;en-US&#x2F;kb&#x2F;digitally-signing-and-e...</a> ; And even for web interfaces there&#x27;s this browser extension called Mailvelope that&#x27;s pretty cool: <a href="https:&#x2F;&#x2F;www.mailvelope.com&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.mailvelope.com&#x2F;</a><p>You see, email does support encryption, just not by default. And the reason for why encryption isn&#x27;t popular with email is because <i>people don&#x27;t freaking care</i>.<p>And the often dreaded protocol that Moxie usually speaks against is XMPP. XMPP apparently isn&#x27;t good for delivering push notifications on mobile phones, but it does supports easy to use encryption. It&#x27;s called OTR: <a href="http:&#x2F;&#x2F;wiki.xmpp.org&#x2F;web&#x2F;OTR" rel="nofollow">http:&#x2F;&#x2F;wiki.xmpp.org&#x2F;web&#x2F;OTR</a> ; Oh, and there are is of course an open-source Jabber &#x2F; XMPP client for Android and it does support OTR, working quite well actually: <a href="https:&#x2F;&#x2F;play.google.com&#x2F;store&#x2F;apps&#x2F;details?id=eu.siacs.conversations" rel="nofollow">https:&#x2F;&#x2F;play.google.com&#x2F;store&#x2F;apps&#x2F;details?id=eu.siacs.conve...</a><p>You see, WhatsApp&#x27;s progress is extraordinary, but only because of popularity, because they delivered encryption to people that don&#x27;t care. Which is quite a feat, except that with another update they can also revert all of that, without users being able to do anything about it. And WhatsApp&#x27;s progress is not extraordinary for its technical challenges.