its point is to warn you of any fixed camera sites or accident blackspots from its database,itll only work on mobile cameras if it picks up radar 'scatter' from a vehicle in front of you.youd have to have the reflexes of superman to stop in time if the mobile camera was pointing at you at the time it detects .it saved me a couple of times when i have been in unfamiliar areas and have been travelling just a tad fast whilst sitting on 9 points but now my license is clean its worth having imo and the gps will show you just how much your speedo is actually out