Detecting slide/touch on an android phone

[mIND.dEcEpToR]

How can I programatically and accurately detect the touch/slide made by a user's touch on an android phone?

I want this to be used as suppose I have two android devices synced with each other. Both of them have anything opened suppose pdf file, music file video file.

Then if suppose in case of sliding the pdf up or down with the touch on one device, the pdf file on the other device is also updated like the slide process occurs automatically on the other device. I hope that I am able to deliver that am trying to achieve!