Here are different ways you can use to connect your phone to car speakers. Most of these methods require a 3rd-party equipment like FM Transmitter but many of the methods let you connect directly to car stereo and play music from your mobile phone or SD card. You can connect your phone to car stereo in the following ways: ● Bluetooth Connectivity ● USB Cable ● AUX cable(3.5 mm audio jack) ● FM Transmitter ● Car Adapter Car adapter and FM Transmitter methods do not allow you to connect phone directly to car stereo because you have to purchase these equipment and attach them between mobile and stereo and then one from the first three methods are used to make a connection.