There's Google Chat, which is really made for companies but available on normal accounts too, and Google Messages, their SMS/MMS/RCS app for Android, which requires that you have an Android phone and a phone plan.
Hangouts is just another client for Google Chat now, Allo is dead, and Spaces is a feature of Google Chat. Meet and Duo are not chat apps really, but there is a pretty clear separation in that Meet is primarily designed for business meetings (competes with Zoom) and Duo is more primarily for personal use (competes with FaceTime)
This is true today, but 3-4 years ago Spaces was actually a completely separate product that was so bad that most Googlers didn't even know it existed.
I have never met a single person, including on the Spaces team, that used Spaces for anything. Ever.
Disco is forgotten usually. From the early smartphone days before Whatsapp and others had firmly won. I believe they even owned Disco.com. I had that app installed way back when.
It was Slack/etc years before those existed. They just couldn't figure out how to market it because there were no reference points at the time, so few could see any reason to use it.
I doubt it's just that. If those things were actually great, people would have embraced them like they did slack.
Consider Google+ also. They had plenty of reference points for that. It was just not very good.
Google tends to abandon development on new projects way too quickly, before they're ready for mass appeal. They probably expect it to explode like Gmail did. But I think they forget they lost a lot of promotors like us when they abandoned the don't be evil thing.
At the time I recommended Gmail to everyone, now I try to get people away from Google :)
Before Slack there was Flowdock (which was never as popular) and I'm pretty sure another I'm forgetting from back then. I used Slack as probably the best-known example.
"We couldn't figure out how to market it" was from an interview straight from the people who made it: The companies they pitched to responded with things like "why would we need this, we have email".
They removed the ability to install the dedicated chat app and moved it all into the Gmail app. Infuriating. Oh, and it opens all links on the built-in chrome browser instead of respecting your default browser settings. There is no option to change the behavior.
> They removed the ability to install the dedicated chat app and moved it all into the Gmail app.
The first part of it is not true (but the second part is true, in that you can access chats from Gmail as well).
I just checked, and Google Chat exists as a separate app on iOS, Android, and web (chat.google.com). Even though the web version redirects to a gmail url (mail.google.com/chat), it is still a separate web version, not embedded into gmail. The only thing it shares with gmail is its subdomain, the page itself has zero mention of gmail or any gmail-related functionality.
>I just checked, and Google Chat exists as a separate app on iOS
I used to have this app installed, then one day it started telling me I had to use the GMail app for chat instead.
I wouldn't be surprised to hear that they were rolling the out the migration to accounts incrementally, or they've reversed course. But I deleted the google chat app because it wouldn't let me use google chat.
I think I may make an independent thread about this soon (but my question may be stupid): why does messages use this paradigm of connecting to one's phone directly instead of accessing texts in some centralized fashion? Is that impossible because only the carrier has the contents of the thread (even though other services can be used to post texts)?