Streaming question

According to Google VNC is a free service but presumably you have discovered otherwise.

  Can the server be controlled wirelessly from a mobile device?

The situation has been resolved. Evidently, VNC offers a free service called VNC Lite. I deleted my prior account and downloaded Lite. The emails they sent notifying me of termination of previous free account did not mention the Lite option.

For windows user RemotePC is included in the OS.  It works really well for me without the addition of a different app

I used to use OpenVNC a number of years ago, and was happy with it. 

It appears to have been forked a few times. A reasonable looking version (which should be free based on the GPL license) is at https://tigervnc.org

i have not used this particular version, but used to be quite happy with OpenVNC