Google has a core set of apps that are part of a package that manufacturers have to pre-install on any phone they sell in order to maintain access to the Google Play Store. For a long time, Hangouts has been one of those mandated apps that’s required in the GMS package for Android smartphones.
A new email sent out to Google Mobile Service partners on October 5th makes some changes to the mandated apps list. Now, Hangouts is no longer required to be bundled with any new hardware. Instead, Duo will be taking its place in the line-up.
Google is trading an app that people primarily use to communicate through text (with video support) with one that only does video (and has no text support). Allo is not included on the list and we can only guess the reason Google is leaving it off is because of how hard they’re pushing Google Assistant as a Pixel-only feature.
Of course, it’s no big deal if you have to head to the Google Play Store in 2017 to download Hangouts on your new Galaxy S8, but it does mean that Google is de-emphasizing the importance of Hangouts in order to make room for Duo and presumably, Allo at a later date.