Garmin and the Smartphone link app

Does this app have voice turn by turn and is that why it's free?

https://buy.garmin.com/shop/shop.do?pID=111441

I have tried the app and found a small problem.
I normally use a Bluetooth connection through my truck radio (a Parrot add on system), which works quite well. Clear voice quality both directions and easy to use.
When I try to use the Smartphonelink all my bluetooth is routed through my Nuvi 3590. Unfortunately the bluetooth call quality on the Nuvi is not the best. I have trouble hearing the other person clearly and the person I am talking to also has problems hearing me clearly.
Of course I may be spoiled by the quality of the sound coming from the bigger speakers in the truck.
I wish there was a way to use both at the same time.
As it is now I have to choose between poor call quality or the usefullness of the app.

I was able to use my BlueAnt bluetooth and the SmartLink at the same time. I just connected the BlueAnt bluetooth first. I think there also was an option in settings on my Garmin 3490LMT to not use the phone features of bluetooth. I actually prefer the Garmin GPS' hands free phone features. Phone quality is equal on both.

Thanks' I'll try it that way and look for the settings.