I see. You know, nostr:nprofile1qqsy2ga7trfetvd3j65m3jptqw9k39wtq2mg85xz2w542p5dhg06e5qpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhszxrhwden5te0dehhxarj9enx6apwwa5h5tnzd9az7qgwwaehxw309ahx7uewd3hkctczcs834 says that there is no network effect with direct messages, but the whole reason I use Signal is because they managed to get half of my family onto their network. Is Keychat or 0xChat intrgrated with Signal's network? Can I can call my family with Nostr? 

 Although Signal is open-source, the Signal app is centralized, and only they can run the servers. We cannot interconnect with Signal. 

 Matti means that as long as two friends are willing to use a particular chat app, they can start using it. This is not possible for microblogging platforms.