[ Plzhow ] Written and illustrated explanations: Duo is replacing Hangouts in Google's batch of preinstalled apps

Instead of swapping Hangouts for Allo, Google is apparently more interested in pushing out a better video call experience than a messaging alternative.

Allo may be the future of Google’s messaging efforts, but it’s Duo that will replace Hangouts as one of the preinstalled options on future Android phones.
An email about the change recently went out to partners that install Google Mobile Services on their phones. This is distinct from the Android Open Source Project, as enabling these services means agreeing to a license with Google that your phone will include this distinct bundle of apps. Basically, all devices with the Google Play Store are “Google Mobile Services” licensees, while other devices that have their own app stores don’t use the Google Mobile Services agreement. We rarely see those products here in the U.S., but Amazon’s Fire tablets are the most popular example.
According to the message details, Google is dropping Hangouts from the list of apps that must be bundled on upcoming phones.

Today, we are announcing that Google Duo will replace Hangouts within the suite of core GMS apps, and Hangouts will become GMS Optional for telephony products. This change will take effect on December 1, 2016.

It sounds like the earlier indication that Hangouts would pivot to an enterprise function is coming to be. The curious change is that it’s Duo, not Allo, that’s become the replacement.
Google must see video calling as the more pivotal market right now, a function that has often been lackluster for Hangouts. Pushing out Duo puts a FaceTime competitor to everyone who buys a future Android phones, enabling them to easily video chat with friends or family members across Android and iOS.
Why this matters: Duo is clearly the cool kid now when it comes to Google’s messaging efforts. I’d expect Allo to get similar bundling treatment at some point, especially since the company faces stiff competition from several messaging apps that are already hugely popular. Until then, it’s up to you to grab it from the Play Store.
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