Help Voice command with locked screen moto G4

[Moto G4 Questio]

I just got my Moto G4, had been using Moto X 2nd Gen. With the Moto X I could open the phone and an app even if the screen was locked using voice command. I can't figure out how to do that with the Moto G4. I want to be able to drive and just say "OK phone, send text to wife" without swiping to open, pressing app etc. The Moto Voice app in the Google Play store isn't compatible with Android 6.0.