Maybe you need spend no money at all.
This might work with the m51?
Worth a try.
https://nadelectronics.com/introducing-the-nad-av-remote-app/
Or if not that particular one just see what is available in the Google play store
This might work with the m51?
Worth a try.
https://nadelectronics.com/introducing-the-nad-av-remote-app/
Or if not that particular one just see what is available in the Google play store