Do you use your smartphone instead of GPS navigation? This is very useful feature, because you have everything at hand and you do not have to buy additional device and worry about maps update. Unfortunately, GPS module and navigation app can dry the battery in your smartphone very quickly.
Seriously, I was using my old HTC Desire smartphone as car navigation and the power consumption was higher than the energy provided from the charger. At the end, the battery was damaged and I had to replace it. SmartNavi application work in the different way. This application does not use GPS module. How is it possible? This magic is due to sensors which are already installed in your smartphone. The app uses GPS only at the beginning in order to determine the initial position, after this the GPS module is disabled and it determines new position basing on the number of steps and the direction determined by the magnetometer (you probably know that your smartphone has a compass). In order to ensure the accuracy, the application has to know your body height and you have to hold the device in front of your body. You can also download offline maps, so as you see, this is very interesting application. As if that was not enough, SmartNavi is free application and it does not display any ads. HERE is the website of this amazing app.