I have no idea about how Vonage works. All my posts relate to MJ. Know nothing about a Vonage app for cells. Only MJ..........SKY, I sure HOPE I'M WRONG. Confirm please: If I set up Vonage with the hardware for my D.R. landline, I can still use the same signal via the app on my smartphone?? If this is true. this might be a great option. I think I'll try vonage.com right now and HOPE I'M WRONG.