Glympse is an app that uses the iPhone’s internal GPS to transmit coordinate information to a website allowing others to track your position on a map. While this sounds like it could be a stalker’s dream app, the idea behind Glympse is that the user can send a “glympse” to an email address or as an SMS text message, inviting only those the user trusts to view their location – and then only for a set time period the user controls. Right now I’m using it to track my wife’s progress as she drives home from Portland in the rain. The app updates her position on the map every 10 seconds or so, giving me a glimpse of her location and speed (so I know she’s safe). Think of this as a peace-of-mind app, and its free no less (at least for now).
Highly Recommended: http://www.glympse.com/