In fact, what you just claimed is wrong. The app waits for the phone to receive the text and there is no way to enter the verification code you receive in another voip app.
This is on top of not being able to use this app on multiple devices.
I have tried that and it didnt work but I'll give it a try one more time.
Regarding multiple devices I mean multiple mobile devices (iOS and Android apps) and not through a browser and extension.