I have been asked by @randylarson how to use an Ipad as a monitor for a hollowing system. Since my set up is at least 2 years old, I do not want to give "old" advice. I would encourage anyone wanting to learn and know more about the use of technology in woodturning to join www.lucidwoodturners.com. But of course, here is an excellent place to ask, we will point you in the right direction. I'm curious to see if @AlanZ has a new way of using an iPad for the hollowing rig.