Optimize TeamViewer for android bandwidth consumption
I use Teamviewer and love it.  Before Teamviewer I used several of the pocket VNC versions you can find for Android.  Some of those version have grayscale options.  The drawback is you will have to forward a port on your router to get VNC to go through.  The other option you may look at is if the program or programs you are looking to control have a web API you can hit rather then the whole PC.  below are some links for the other programs to control your PC via ANDROID.

EDIT: thought about it a little more and remembered you can use LogMeIn Hamachi and VNC.  Set up the LogMeIn Hamachi client on the PC you want to connect to, then you can VNC into the Virtual IP the Hamachi client provides.  This will enable you to use the advanced display setting in some of the VNC clients.  Hamachi


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