Radar detecs are illegal in my state too...but...
we have one for when we travel "out of state"...
Used trapster for about a week...not quite as smooth and seamless as an app of this type to be, esp for the driver to handle. Maybe good for a passenger to be "co-piloting" but the wife would rather sleep.
Using this on a mount doesn't seem very feasible since the buttons in the app are small...so on the go reporting does not work out quite right.
Majority of the traps were there at one time or another...and if you look at the map of your frequented areas...you'll notice the "hot zones" where the police or high way patrol like to set up. MAY NOT be the exact spots everytime, but within the half to quarter mile stretch seems reasonable.