Comment: I use Lookout on my smartphone

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I use Lookout on my smartphone

Which has a "find my device" feature. I've only had to use it once before. I was unsure if I locked my car door and couldn't find my door. I looked in my car quickly and couldn't locate the phone. I was able to borrow a coworker's smartphone and the cellphone sent out its current location (which was, in my car). A more thorough search revealed it fell below my seat.. Certainly a little peace of mind, especially if it allows you to file a police report and potentially a claim against insurance.