When you’re using a cell phone while driving around town, it operates on DC, or direct current. This is because the battery inside your cell phone stores energy in the form of direct current, which powers the device.
Additionally, if you’re charging your phone in the car, the vehicle’s charging system typically converts the AC, or alternating current, generated by the car’s engine into DC to charge your phone’s battery. Thus, while the power supplied by the car’s alternator is AC, the phone itself runs on DC.
In summary, cell phones primarily use DC current to function, whether they are being charged or used on the go.