In Google’s line of products, Allo and Duo are aberrations in that they don’t work with your Google Account, instead relying on your phone number. That looks set to end with screenshots surfacing of Duo requesting your credentials to link to your account.
The support for account linking in Duo is backed up by a support page, which says the feature will only be on Android – though it’s always possible it will come to iOS users too. From the looks of things, linking your account to Duo will allow you to find other people, and let them find you simply by having your Gmail or Phone # in their contacts
The linking appears to be in version 31 of the app, though it’s not available to all users so it’s likely the usual slow Google Trollout of a new feature. The folks over at 9to5Google have gotten it working, and we can see what it looks like in the settings, though they note they haven’t been able to add, or be added just by their Google account.
Adding your Google Account to Duo could open the door to other options such as multi-device support, a feature that’s sorely missing from both Duo and Allo. We’re hoping it won’t be too long until we see this support go live, so keep an eye out.