My first thought would be a little process running on a server not on your network that pulls the download every so often, say once a day, and texts you if it i

My first thought would be a little process running on a server not on your network that pulls the download every so often, say once a day, and texts you if it is different. You'd expect a text after you push your new version, but if you get one out of the blue, then you'd know something was up.