Connection string to MS SQL database android/iOS app

Firstly make sure you have the necessary permissions and that your SQL Server is configured to allow connections from your Xamarin Forms app.

Then make sure you have the correct dependencies and configurations in your Xamarin Forms project. Ensure that you are using the right SQL Server package or library for your Xamarin Forms.

To set up a connection in your Xamarin Forms using ADO.NET as for instance you will use as an example the following (as you supplied no sample code for us to make sense) -

using System;
using System.Data.SqlClient;

namespace YourNamespace
{
    public class DatabaseHandler
    {
        private static string connectionString = "Data Source=sql.bss-solution.info,1433;Initial Catalog=ABC 2023;User ID=admin;Password=somepass;Connect Timeout=60";

        public void ConnectToDatabase()
        {
            try
            {
                using (SqlConnection connection = new SqlConnection(connectionString))
                {
                    connection.Open();
                    //Message if connection successful, you can perform database operations here...
                }
            }
            catch (Exception ex)
            {
                //Handle any exceptions/errors, log them, or display an error message...
                Console.WriteLine($"Error: {ex.Message}");
            }
        }
    }
}