I need a device about the size of a phone with 2 buttons, the device will be used to let a server know the outcome of an event (2 possible outcomes). A mobile phone app would be the obvious choice but I want to reduce the latency as much as possible and it also needs to be more reliable than mobile internet.
I was thinking that it might be possible to create a device that sends the outcome by a radio transmitter to a receiver connected to a computer up to a 1km away with a fibre optic internet connection.
the device would need to operate for several hours.
is this realistic? how much knowledge and skill would be needed to create something like this?