I am wondering to know if I rather to not integrate google or other maps into my application using API keys, is there a way to place a button in the app that opens the devices default map and user can search and find a desired place, then the app closes the map and picks the location [long,lat]/address for it's internal usage?
Is it possible to have a location/address picker without using APIs?
If you want to pick lat/long without Google Maps API you can use flutter_map plugin that developed by fleaflet. You can generate map on your app screen with Google maps view or Open street view. And also you can pick lat/long when touching the map.
Here is the documentation https://docs.fleaflet.dev