Using a Navigational System is very simple just load the map, set a destination and the system will even tell you over the speakers when and where to make a turn. It also displays your position on a screen. Modern navigation systems also include all manner of telephony, including internet (from where the maps are loaded).
Using the road database, the unit can give directions to other locations along roads also in its database. In case of missing a turn it also calculates the distance required to get on the same route. Dead reckoning using distance data from sensors attached to the drive train, a gyroscope and an accelerometer is very reliable; as GPS signal loss or cross – networking can occur due to urban traffics and over use of network.
The color LCD screens on some of the Navigation system technologies can be used to display television broadcasts or DVD movies. A few systems of these are integrated with mobile phones for hands – free talking and SMS messaging which can be done using Bluetooth or Wi – Fi (Direct). Now – a – days many cars come with integrated systems, some sorts of which can be taken out of the car and can be used as hand – held while walking. Vehicles produced by Cadillac, Subaru, Lexus, Cadillac's parent company General Motors and Lexus' parent company Toyota lock out many of the features of GPS while the vehicle is in motion. The manufacturers claim that this is done as a safety measure to avoid the driver being distracted. An Australian man successfully got off a speeding conviction after evidence from the GPS navigational track proved that he did not exceed the speed limit, in around July 2007. A vehicle can get itself retrofitted with a GPS navigation device unit if it did not originally have one. There are three ways in which this can be done: using a Portable GPS, or getting a Original factory equipment or getting it from Aftermarket.