Lee, do you mean the navigation app?
If so, then you have to keep in mind that tha navigation app can only handle routes made for the Here maps. If you use an other map, Openstreet or Tom Tom, than it tries to project that route in the Here map. But if there is a difference in the maps, the navigation app makes the best of it. But most of the time its not what you want.
If you make a special bike route, for sure you can not use the navigation app, because on the Here maps are no bike paths available. So the app send you to the moon and further.
Best regards, Baltus