Perhaps this information might help you to finish your Project.
Other Navigate Solutions
App Inventor 2 developers can provide something similar using the Map component but without the directions display or can use OpenStreetMap without the Map Component. You can draw an OpenRouteService (ORS) type display without using the Navigate component. The method described in the above link draws the route but does not provide the turn by turn directions. This might work on iOS where the Navigate component will not (it will work on an Android).
Another alternative to providing turn by turn map direction advice is the Google Directions api . Use it with a Google Map API key . Again, this might work with iOS.
Another way to provide directions: Use an ActivityStarter and intents to open Google’s Navigator app. This link provides basic information https://groups.google.com/forum/#!msg/mitappinventortest/3d7bFyGM508/pNsqAb9hBQAJ
The link also provides more advanced options to provide route information too. This advice HOW TO use the new Map Control to plot a route on a map and post driving distance and time for that path. is useful too.
Again a different way is OpenStreetMap without the Map Component using OpenStreetMap by using a WebViewer (mentioned above)