user107459: I was surfing on the web and trying to find a chat app that uses Bitcoin address instead of phone numbers or any other identifier. Do you know about any project in this field?

user100690: The idea was around for some time, and as Pieter mentioned, using addresses without any additional obfuscating seems like a bad implementation.
There are few other projects, the one that is most serious is Microsoft's ION decentralized identity project. It's not the chat-app itself, rather the way of signing into apps using bitcoin-generated identity.
When it comes to chat apps, there is a pretty rapid development in the field of lightning network. As messages on LN are onion-routed, it seem to be a good idea for privacy-preserving communication.
There are two projects I heard about, self-custodial Juggernaut and centralized (so what's the point) Sphinx.
I'd be very hesitant in using these solutions, they are working as untested, beta-version projects, so they may not be as stable and secure.

107459: <p>I was surfing on the web and trying to find a chat app that uses Bitcoin address instead of phone numbers or any other identifier. Do you know about any project in this field?</p>
 100690: <p>The idea was around for some time, and as Pieter mentioned, using addresses without any additional obfuscating seems like a bad implementation.</p>
<p>There are few other projects, the one that is most serious is <a href="https://bitcoinmagazine.com/articles/microsofts-ion-is-an-open-source-bet-on-bitcoin" rel="nofollow noreferrer">Microsoft's ION decentralized identity project</a>. It's not the chat-app itself, rather the way of signing into apps using bitcoin-generated identity.</p>
<p>When it comes to chat apps, there is a pretty rapid development in the field of lightning network. As messages on LN are onion-routed, it seem to be a good idea for privacy-preserving communication.
There are two projects I heard about, self-custodial <a href="https://www.getjuggernaut.com/" rel="nofollow noreferrer">Juggernaut</a> and centralized (so what's the point) <a href="https://sphinx.chat/" rel="nofollow noreferrer">Sphinx</a>.</p>
<p>I'd be very hesitant in using these solutions, they are working as untested, beta-version projects, so they may not be as stable and secure.</p>
