Sample Audio Recording service used for a Xamarin Forms application to record & play audio even if the user goes to the background. I expected to inherit from Android's Service, but I didn't need to do that

AndroidAudioRecordingPlaybackService.cs

using Android;
using Android.App;
using Android.Media;
using Android.OS;
using Java.IO;

[assembly: Xamarin.Forms.Dependency(typeof(BackgroundRecord.Droid.AudioRecordingService))]
[assembly: UsesPermission(Manifest.Permission.RecordAudio)]
[assembly: UsesPermission(Manifest.Permission.ReadExternalStorage)]
[assembly: UsesPermission(Manifest.Permission.WriteExternalStorage)]
namespace BackgroundRecord.Droid
{
    public class AudioRecordingService : IAudioRecordingService
    {
        MediaRecorder _mediaRecorder;
        public void Record()
        {
            CheckForPermissions();
            _mediaRecorder = new MediaRecorder();
            _mediaRecorder.Reset();
            _mediaRecorder.SetAudioSource(AudioSource.Mic);
            _mediaRecorder.SetOutputFormat(OutputFormat.Mpeg2Ts);
            _mediaRecorder.SetOutputFile(GetFileName());
            _mediaRecorder.SetAudioEncoder(AudioEncoder.Aac);
            _mediaRecorder.Prepare();
            _mediaRecorder.Start();
        }

        public void Stop()
        {
            _mediaRecorder.Stop();
        }

        MediaPlayer _mediaPlayer;
        public void Play()
        {
            _mediaPlayer = new MediaPlayer();
            _mediaPlayer.SetDataSource(GetFileName());
            _mediaPlayer.Prepare();
            _mediaPlayer.Start();
        }

        private string GetFileName()
        {
            var path = Environment.ExternalStorageDirectory.AbsolutePath + "/MyFamily/";
            var dir = new File(path);
            if (!dir.Exists())
                dir.Mkdirs();
            var myfile = path + "filename.3gp";
            return myfile;
        }

        private void CheckForPermissions()
        {
            if (!(MainActivity.Instance.CheckSelfPermission(Manifest.Permission.RecordAudio) == Android.Content.PM.Permission.Granted &&
                    MainActivity.Instance.CheckSelfPermission(Manifest.Permission.ReadExternalStorage) == Android.Content.PM.Permission.Granted &&
                    MainActivity.Instance.CheckSelfPermission(Manifest.Permission.WriteExternalStorage) == Android.Content.PM.Permission.Granted))
            {
                MainActivity.Instance.RequestPermissions(new string[] { Manifest.Permission.RecordAudio, Manifest.Permission.ReadExternalStorage, Manifest.Permission.WriteExternalStorage }, 1);
            }
        }
    }
}