Is that Windows on the phone ? If yes, then I'm not sure
If it's Android, then I use Track Navigator - it's free and reads the direction text to you (you can edit it first in Plotaroute.com before downloading the route).
You could also use OSMAND - this app allows you to download maps too so you can see where you are. It's more chatty than Track Navigator and although it doesn't actually read the text to you, it tells you every bend and turn.
I use one earphone, turn off the screen and just listen - that works best for me
If I create a route and download the GPX file, which is the best app to load into for my mobile phone? I am on windows.