John Kilcline, a Google product manager, said in a Google+ post that the company “decided to take what we learned with Spaces, and apply it to our existing products.” Although Kilcline wasn’t specific, one of the products that could implement Spaces’ features is perhaps Allo.
Spaces allowed users to easily share content and commentary on any specific topic. The app was more of a forum-like service than a true messaging app. Much like creating specific topic-oriented groups on Facebook, Spaces was meant to be used to create small groups where you could invite friends or co-workers to discuss about specific topics. And being a Google product, users could bring in Google searches, images and YouTube videos directly into Spaces.
Kilcline added in the post that Spaces will now move into read-only mode before it completely shuts down the service on April 17. It looks like Google is slowly abandoning some of its stagnant applications, and perhaps Hangouts, which is slowly being replaced by Duo, could be next.