- Edited
Rnd3sB3g13rng I might be wrong, but I don't think that's possible. When you connect the same number on a second Signal (or Signal adjacent) app, the first phone will be disconnected. This seems to be the case with Molly as well.
That said, my understanding is that you could have two different Signal accounts/numbers on the same phone by using the official Signal app for one number, and Molly for another.
(Someone can correct me if I'm wrong about that last point)