I'd like to download a large area onto my phone with my heatmaps so I can access this from the trail when I have no service.  I can do this on Trailforks but it does not show my "private" routes. 

Is there a way to download the  Strava map locally to my phone and still have access to trails/routes that I recorded when I open the app and not "in service"?  Again, the trails that I want to access on the map would be private not public.

Thanks in advance