I built a slideshow control system for a class project using nearly the same approach. A user uploads a slideshow or authors it online and connects a phone/device via a QR Code or URL to control the presentation. The controller uses websockets to communicate with a nodejs server for events like previous/next, a touch-screen based laser pointer, and presenter notes. I was amazed how responsive the touch movements translated to moving a dot on the screen through a remote node server.

We didn't use any accelerometer events, but touch events worked seamlessly on iOS and Android.