Aim - to remove or reduce gratuitous video and music downloading.

To give the reader control (ie a button to push) of what gets through the data limit set location.

I don't actually know where in the network that is.

I read of a monitoring app to see if urls are online, could that be used/adapted to prevent gratuitous downloading?
(by sending an x to replace specific suffixes which can be over-ridden if downloads are needed )

The entire app being optional in the first place.

I think I will cc this query to as many developers as I can find.