secure chat3 chat app2 agora video call1 anonymous chat1 anonymous group1 anonymous messaging1 chat room1 cross platform1 dark mode1 electron app1 encrypted message1 ephemeral messaging1 file sharing1 firebase backend1 firebase chat1 flutter chat app1 group chat1 lan communication1 local storage1 mightychat1 notifications1 offline chat1 one to many chat1 private messaging1 react desktop1 real-time communication1 realtime chat1 realtime messaging1 scan qr code1 social chat app1