Naven
Answers
Do you need an account to join a Naven channel?
You need one to post. Opening the link works first, and signing in takes an email address and a six-digit code — no password to choose, no phone number, no app to install.
The friction of joining is what decides whether a link actually works as an invitation. A link that leads to an app store, a download and an account creation form loses most of the people who click it.
Naven's version is: the link opens the channel in the browser you tapped it in, and signing in is one address and one code.
What this means for whoever sent the link is that it is worth sending to people who have never heard of Naven, which is not true of most invitations.