OnePlus announces Google Duo will be officially integrated into OxygenOS‘ dialer, contacts, and messaging apps Duo and Allo were initially announced back at Google I/O 2016. While the Google Assistant-infused messaging application didn’t receive much love, the video calling platform gained a lot of popularity. It has over one billion downloads and 3 million mostly positive reviews on the Google Play Store. It even comes built-in to most Android devices. Google has also integrated it in the Phone application