We keep trying with it. Last ride went really well until the phone kept going to sleep. Explanation below. I used it to follow a route, not as a navigation device, just as I did VR. Create plan and then turn it into a route online and then syncronise the phone if you can find the button! Find the route and it will be displayed on the map. Download the map tiles. Then, if again you can find the button, select offline mode, I have a suspicion that it is only there in nav mode. (That said we rode in online mode and there was no data usage so maybe it knows the map tiles are local?) Do not select nav or tracking just touch the location icon, lower left and the map will centre on your position and annoyingly zoom in. A two finger tap will zoom out. A single finger double tap will zoom in. And as we have just found a single finger single tap will make the map go full screen. Brill. However if in zooming in or out you knock the screen off centre then the phone will go to sleep after a short while. As we now have a full screen map with no icons it's no longer as easy as touching the location icon which in any case will mean going through the zooming in palaver.
Hope this helps someone and that the eggs taste great Grandma.