Can i use my android device as a windows touch pad? i want to use my android device as a touch pad for windows like ipad and other tablet device do for designing what should i do for this problem
There are plenty of ways to do this. Here is what I recommend:

Remote Mouse: It's an Android App/Windows Program that serves that exact purpose, and has a clean UI.
https://play.google.com/store/apps/details?id=com.hungrybolo.remotemouseandroid&amp;hl=en

You can also use a remote desktop app like Splashtop or Chrome Remote Desktop, these will let you actually display your computer screen on your Android device no matter where you are.