title: Flutter offline map routing
body: <p>while developing my Flutter application(Android only, no iOS support) I ran into a problem.</p>
  <p>Use-case is that a user while online downloads a map route directions from Google Maps API/MapBox(yet to be decided which will be used in final build) in JSON/XML format and saves on device. Then while offline use this route to navigate.</p>
  <p>Application is aimed at hikers, runners, cyclists etc. so there is requirement to be able to correctly navigate user if he pre-downloaded the route.</p>
  <p>My problem is that I can´t find right plugin for Flutter to do the navigation. The application is final thesis in my university studies, so the requirement is to use only Flutter and Flutter plugins to do the work and donť write or use any Android native code/SDK/plugins.</p>