Hello.
I am a GIS expert and Web&Mobile developer.
Since 10 years before I have been developing GIS applications.
I graduated GIS special education course and I have rich experiences for development Desktop,Web and Mobile GIS applications.
as a GIS developer, I can develop any kind of GIS application based on ArcServer,GeoServer and GoogleMaps,Mapbox,PostGIS and PostgreSQL and MS SQL.
I checked your requirement and I know as well about Google Map and OSM.
I would like to heard from you.
thank you.