Text and video chat from Google. Hangouts was originally part of the Google+ social network but was separated in 2015. In 2017, Google introduced new versions of Hangouts for the enterprise.
Hangouts Chat was designed to support project teams similar to the Slack app; however, by the end of 2022, all Hangouts conversations were transferred to Google Chat. Hangouts Meet, later renamed Google Meet, provided videoconferencing. See Google Chat
and Google Meet
Google Allo and Duo
Geared to consumers, Allo was a chat app, and Duo was a video calling app. Whereas Hangouts required a Google account, Allo and Duo were based on the user's phone number. See Google Allo
and Google Duo