DatabaseService.cs

 public class DatabaseService : IDatabaseService
    {
        public string GetDatabasePath()
        {
            string dbPath = "";
            if (Device.RuntimePlatform == Device.Android)
            {
                dbPath= Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal), AppConstants.DatabaseName);
            }
            else if (Device.RuntimePlatform == Device.iOS)
            {
                dbPath= Path.Combine(Environment.GetFolderPath(
                Environment.SpecialFolder.MyDocuments),
                "..",
                "Library",
                AppConstants.DatabaseName);
            }

            return $"Filename={dbPath}";
        }
    }