Wouldn't you have to add another smart phone to your plan? That can't be cheap!
There was a fantastic article on Snipers Hide (IIRC) that outlined the entire process with a video camera, transmitter power source etc that was recieved at the shooting spot & viewed via laptop. Cost was actually quite reasonable & with the available equipment the builder was confident reception could be possible up to 1 mile... Part numbers, websites & costs were all included in the post.... very good read.
I am interested in your idea though, not nearly as much gear to haul around & worry about perforating!