I think this idea and smart phone/tablet control (Bluetooth) of lights/sirens are both cool "in theory," but are not very realistic or practical for use on most EVs.
First off, I'd be squinting to see what each little button is on the RVM (probably a lot longer than it'd take for me to glance at a normal control head mounted in the dash or center console). Aside from the audible warning buttons, I really don't think there are any buttons that we need quick access to while driving (I mean, how often do you need to look down to control the TA, TDs, Alleys, etc while you're driving a hard code 3 at like 70 mph?? Most of the accessory buttons are usually stuff that I only activate when pulling up/parked on scene). Also, I feel that many of us quickly get acclimated to where the center console controls in our vehicles are without having to look down; although it was initially frustrating when our SUVs went from the Whelen 295 controls (with the siren knob in the middle was an easy "reference point") to cencom golds a while back, I eventually was able to control the cencom without having to look down after getting used to the feel of it & knowing where the 5 siren/horn buttons. For that reason, I personally never liked the idea of tablets being used as controls b/c there is no feel of a button or switch
