OpenStreetMap or Google Map Android App with Offline Navigation

We need a highly skilled Android developer to create a user-centric mobile application integrating the OpenStreetMap service or Google map with an offline map feature.

Features required:
-Showing pre defined points: Need to show pre defined points on offline map using the lat & lang values
- Offline navigation: a key functionality should be the provision of turn-by-turn directions to the pre defined points. This will allow users to navigate without an internet connection.
- Route optimization: Enhancing user experience, the app should optimize routes, calculating the most efficient path based on the user's current location and pre set destination.

Ideal skills and experience:
- Proven expertise in Android development.
- Proficiency in working with Google map or OpenStreetMap or any other offline map services.
- Significant experience in developing mobile apps with navigation features.
- Familiarity with implementing route optimization algorithms and geolocation services.

We are looking forward to receiving proposals from qualified specialists passionate about enhancing user mobility.