Using a mobile phone as a satellite navigation aid while driving will remain legal after Transport Minister Steven Joyce slapped down an officials' ban. Many "smart phones" now come with GPS chips and road maps installed that allow them to work as SatNavs. In a statement on Friday, Transport Ministry spokesman John Summers said the Road User Amendment Rule restricting the use of cellphones in cars, due to take effect in November, meant drivers would not be able to look at a navigation aid on a mobile phone when driving, even if it was mounted in a hands-free kit on their dashboard. But yesterday afternoon, Mr Joyce said: "It is not the intent of the rule to make it illegal for motorists to use the satellite navigation or music functions of their cellphones, provided these are mounted in the vehicle and are manipulated infrequently." The rule would be amended to make that clear. Mobile phone company 2degrees chief executive Eric Hertz this month admitted rear-ending another vehicle at an intersection while glancing at directions on his iPhone, mounted on a hands-free kit in his car.