Google Duo was a video calling app that allowed people to call someone from their contact list. Launched August 16, 2016; shut down June 1, 2022 — it lived 5 years. One of 16 Google products killed in 2022. Google Duo was a proprietary voice over IP (VoIP) and videotelephony service released in 2016 by Google and merged into its Google Meet product in 2022. It was available for Android, iOS and web browsers. It let users make and receive one-to-one and group audio and video calls with other Duo users in high definition, using end-to-end encryption by default. Duo could be used either with a phone number or a Google Account, allowing users to call someone from their contact list. Wiki link Data: Killed by Google (killedbygoogle.com, MIT).