I want an app that helps you find your car in a crowded parking lot, but I have no idea how it would track your way back. Any thoughts?

Kind of self-explanatory. Personally, I can never in my life remember where I parked my car in the mall parking lot. Many times I have had to search for my car for way longer than I should have. I would love an app where you can press a button when you park your car, and it will help guide you to the car when you press the button again. I have no idea what kind of technology would be required to make an app like that, but it would be really helpful.