The App Store version of the app has the following features, per the App Store:
Description
Google Duo is the highest quality video calling app*. It’s simple, reliable, and works on smartphones and tablets.
Features:
Simple interface
Pick a contact and jump right in, with a simple interface that makes video calling as easy as one tap.The highest quality video calling app*
Experience more reliable video calls with excellent video quality whether you’re on Wi-Fi or on-the-go.Works Cross-Platform
Duo works across both operating systems on smartphones and tablets, so you can call and hangout with friends and family using just one app.Knock Knock
See who’s calling before you pick up with a live video preview.Video Messages
Friend can’t answer the phone? No problem. Leave them a video message for them to call you right back. With a video message, you can still capture everything about that moment you wanted to share.Voice Calls
Make voice-only calls to your friends when you can’t chat over video.
Google Duo is free, and is available for iPhone and iPad device in the App Store. [GET IT HERE]