How can I add an AUX port to my Audi 80 car stereo?

I recently bought a secondhand Audi 80 and it does not have an AUX port for my phone. Is there a way to add one to the stereo system, or do I need to invest in a new stereo?

You can try using a FM transmitter. They are easy to set up and relatively affordable. Just plug it into your car's power outlet and connect your phone via Bluetooth or a headphone jack. It may not offer the best audio quality, but it's a simple solution.