The new app, announced in May, is being released Tuesday as a free service for phones running on Google’s Android operating system as well as Apple’s iPhones.

Like FaceTime for iPhones, Duo only requires a person’s phone number to connect. Many other services require both participants to have account logins to use their video-calling options.

“Today, we’re releasing Google Duo — a simple 1-to-1 video calling app available for Android and iOS,” the search giant said in the blog post. “Duo takes the complexity out of video calling, so that you can be together in the moment wherever you are.”

To refresh, Duo is based on phone numbers, meaning it just requires your phone number to get started, and lets you connect with people in your phone’s contacts list. The app is built to work even if you are on a slower network. It also switches between Wi-Fi and cellular data automatically without dropping your call.

Simple interface

Duo is simple from start to finish. To get started, all you need is your phone number and you’ll be able to reach people in your phone’s contacts list. No separate account is required, so you can sign up in just a few steps. From there, you can instantly begin a video call with a single tap.

Fast and reliable

We all know how it feels when a call fails to connect or when video gets choppy. We’ve built Duo to be fast and reliable, so that video calls connect quickly and work well even on slower networks. Call quality adjusts to changing network conditions to keep you connected — when bandwidth is limited, Duo will gracefully reduce the resolution to keep the call going smoothly. For video calls on the go, Duo will switch between Wi-Fi and cellular data automatically without dropping your call. You can start your call at home, and continue seamlessly even when you head out the door.