You’re in a big parking lot, like at an airport, and want to easily find your car when you return.
Just use Google maps on the iPhone plus the free Evernote app.
When you park the car, open up the map app. Your current location is indicated by the blue dot. Press the blue “>” icon at the right of “Current Location.” The Info screen will appear, choose Add to Bookmarks, and put in a logical name for it, like “airport parking.”
Then, take a picture of where the car is (with aisle and row) and store it as an Evernote. You can also add a text note or voice note.
When you return, go into the map, hit the bookmark icon to the right of the address bar and choose the bookmark you saved. You’ll be able to find the car easily, especially with Evernote to guide you.
On a recent first trip out of Las Vegas, I parked in extended parking, and found the car easily using this. I also took a photo of the shuttle bus and stored it as an Evernote, so I would know what it looked like when I returned.