Google Duo Introduction: how to use it safely and privately
A helpful introduction on the advantages and disadvantages of Google Duo, how to use, and privacy information.

why Google Duo?
Google Duo is unlike other video calling services in that it is extremely straightforward and easy to use. All you need to do is sign in to the app, select a contact you wish to call, and tap the video call button. The interface is as minimal as it gets; you just see a list of contacts that have Duo installed, and there’s the option of inviting your friends over for those that don’t already use Duo.
Advantages
See who is calling by using the Knock Knock Feature
User friendly and intuitive interface
End to end encryption
Free on both Apple and Android devices
Disadvantages
No instant messaging, only video and voice calls
Requires a phone number to get started
How to use Google Duo
Mobile Compatibility
Android
iOS
Desktop Compatibility
Windows
macOS
Safety and Privacy Concerns
Video conferencing spy bug
Similar to the FaceTime bug where callers can see and hear from the recipient’s device before they’ve actually accepted the call, Google Duo also had this issue. Interestingly enough, this issue was discovered by a researcher working for Google Project Zero, rather than a user, and the issue has since been fixed. This goes to show that you should always exercise caution when using any type of software.
Mozilla tips on how to control your data
Google provides various privacy controls, accessible via Google Privacy tools. There are several clearly defined ways to delete personal data, including deleting data from separate services or deleting a whole Google Account. The retention periods are also listed in the Policy. Google also offers a possibility to set chat retention rules via its Vault service. For Google Duo, hosts can start calls, mute, and stop calls. Once someone is admitted into a meeting, they automatically have the ability to present.