I'm using a google pixel 2 and the app is not connecting with the amp although the phone IS already connected to the amp.

I've tried my wife's samsung s9 and it works ok. 

 Edit. Ok, Now It's working. But not only i had to forget the device, I had to do a Bluetooth, Wifi and Mobile reset. And after I reinstalled the app. 

The reset option is located in Settings>System>Advanced

So everyone else having the same problem and still not working after forgetting the amp on Bluetooth settings and reinstalling the app should try this instead.

Can't be more happy with the amp

I hope this can help anyone.