Google’s Duo launched not too long ago and its messaging partner, Allo, was announced with it at Google I/O this year. So far we haven’t been told when Allo is going to launch. Known trusted leaker, Evan Blass, posted a tweet saying “Hello, Allo (launches week).” There aren’t any other details or exact release date given. Some other rumors have said September 21.
Like Duo, Allo uses your phone number as your identifier rather than a Google account like Hangouts uses. Anyone with your phone number will be able to contact you on both apps.