To all the people out there, always in for latest innovations, Google Duo is the Android’s latest answer to FaceTime, enabling people to make simple and stable video calls to friends and family. In addition, there is also a new update placed by Google, which allows users to receive calls made by the duo app on any Android phone, even if the user doesn’t have the app actually.

As per this update, audio and video calls would pop up on some Android phones even if the app is not there. Though right now it’s not clear what the criteria are exactly in all probability having the phone number registered with Google seems to be a part of it.

The entire process is initiated through something called App Preview Messaging, and it works with a background app called Google Play Services. This tech allows some basic bits of an app to essentially operate as a part of Android, so users can get in touch with people no matter what messaging apps have been installed.

Knock, knock, who’s there?

One of the most striking features of this Google Duo is the ‘knock knock’ feature that lets the user see the one calling on screen even before answering, as a functionality. Also, at the end of a Duo call, users are questioned if they want to install the app, if not installed already.

Now, this won’t work while making calls to iPhones but definitely makes life a little easier for the Google Duo users.

Google has not officially declared anything about the update right now, but it had continuously pushed Duo and the text-based Google Allo as its messaging apps of choice, even with the likes of Google Hangouts behind the back.