And there's another app from Pete Warren that takes all the data from where your iPhone has been (you did know that it stores this information for the past year, did you?) and consolidates it into a map.
Maps also quickly go stale as the physical world changes: new streets are added, buildings are built or torn down, and floods and other natural disasters change the face of the planet. So mapmakers are looking to outsource these updates to the people who live nearby and who are interested in keeping things up-to-date.
Google recognized this and announced in April that anyone could submit an update to its maps with its MapMaker service. These updates are posted to the main Google Maps collection, starting with US-based locations; Each entry will be reviewed before being posted for accuracy. And, this being Google, you can watch in real-time as people add points of interest to Google's maps. This is a clever enhancement, because it means that Google's maps are getting more detailed and accurate every minute, as hundreds or thousands of users annotate and update the maps.
But Google isn't the only one making it easy to add crowd-based content to its maps, and indeed Microsoft's Bing, Yahoo Maps, and MapQuest have their own collection of maps. The open source community has also gotten behind mapping, and there are a number of tools that make it easy to collect geographic data from mobile phones and publish it across the Internet, including Crowdmap.com, OpenStreetMap.org, and MapServer.org. These services promise to do to maps what WordPress and Blogger did for blogging and Web sites in general. A good comparison of several mapping services can be found at Wikipedia.
These tools make it easier to do things such as collating all pictures taken at a given landmark, showing the progress over time of development of a particular block. You could also easily create a map that pinpoints all of your corporate office locations so that customers can find the closest one by either entering their ZIP code or clicking on a map. Before open source mapping came along, you would have to learn Google's or MapQuest's particular programming interfaces and write code that would only work with that individual mapping provider.