See all your Google Contacts on a Google Map
Want to know where you friends and colleagues are? The all-new Map My Contacts app will help you quickly visualize the location of your Google contacts on a world map. It reads the postal addresses of people from your Google Contacts and puts them all in a Google Map using a simple Google script.
Publish a Map of Google Contacts
It takes one easy step to turn your address book into a Google Map. If you are Google Chrome user, you can install an add-on or you can click here to directly access the “Map My Contacts” web app in any other browser.
The app will require authorization because it needs to read the addresses of your Google Contacts and it needs access to Google Drive for saving the generated map. It is an open-source Google Script and you get find the entire source code on ctrlq.org published under the MIT License.
Once you have authorized and granted access, the app will run for a few minutes, depending on how big your address book is, and generates a Google Map embedded in an HTML file. A KML file is also created in your Google Drive with markers (or placemarks) for every contact and you can double-click to open this file inside Google Earth.
Also, if you are not using Google Contacts as your primary address book, you can still use the apps to map your contacts. Just export the contacts data from your existing address book (like Outlook or Yahoo Mail) as a CSV file, import the file into Google Contacts and run the app again.
Internally, the Google Apps Script reads the home and work postal addresses of your Google Contacts and then uses the geocoding service of Google Maps to transform these human-readable addresses into latitudes and longitude values. These points are then put in a KML file (see sample KML file) that can viewed inside Google Earth or Google Maps.