That's too much work for little to no gain, anyone who runs a mining farm should be able to afford a PC or laptop of some kind, if the farm has many gears then tracking them on a mobile app is going to be a nightmare, if it has a few then monitoring apps are not really needed to begin with.
Not trying to discourage OP, but the best question to ask yourself before attempting to sell a new piece of software is "why would people use it", since 99% of the users won't be to able to safely check if the software is "honest", chances are -- most of them won't run it anywhere near their mining farms, all you need to have a miserable couple of months ahead is a nightswitcher or antbleed virus infecting a dozen miners on your farm.
I don't understand what you want to say about the laptop. Do you think that a large miner will not have enough budget for several computers?
The main control is usually on the computer, but the chief and duty engineers usually have an additional application that notifies about problems and failures during mining so that it reacts faster.