It just so happens that we were talking about a similar issue to your cousin's in another thread:
http://forums.cnet.com/5208-7811_102-0.html?forumID=78&threadID=314534&messageID=2897021
Hello all, I would like to have some advice from you people. I have a cousin with whom I mostly go out in the city. She takes her car out most of the times but the trouble strikes when often she forgets the place where she parked the car. I usually remember but it so happens that I get down and she goes on to park it. She is just so engaged with her iPhone that she almost forgets where she get off and everything about the car. I need to take care of this problem and so I would need some advice from you people.
Any help will be appreciated.

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