Just start the app when you park, wait a moment for GPS, and save your current position. That's it! When you want to get back to your car, just re-start Car Finder, allow it to get GPS again, and tell it to find your car! Very simple and easy to use. Extremely light on memory and phone resources in general, so it a good choice for entry-level or older phones.
Please try this free version first. If you don't want the advertisements, then please consider the paid version; which has identical features except no advertisements. It's very cheap, and will help me buy a half-decent phone! This version requires the Internet permission to load Ads.
The paid version has no extra features.
Uses Google Navigation to get you back to your car.