laggy and unstable

I tried this app on both my iPad Air 2 and iPhone 6 and it was very laggy. Any windows moved into the extended display area jerked about as I dragged them. It crashed once about a minute in. Not really an app I want to go any farther with. I gave it 2 stars because the image quality was good.

JFra88 about GoodDual Display for Mac, v1.4