Android app and device contacts list

[BillH]

I am using the Android app on a Samsung Galaxy phone. I am unable to make calls with Magicjack using my contacts list. With the Magicjack app active the phone will always go to cellular for the call. There are settings that will allow me to configure the phone for when the Internet should be used for calls, but these settings will not direct a call made using the contacts list to the Magicjack app. Do I have to enter info for a SIP account in order use the contacts list, and if so what info would I have to enter? I should mention that I can use the dial pad to make Magicjack calls without a problem.

Any help would be appreciated.