Next to Search and Gmail, Google Voice might be one of the most valuable of Google’s applications, particularly if you are like me and have multiple mobile phones and mobile phone numbers. The Google Voice service routes phone calls and provides a voice mailbox. You can also use the service to place phone calls and send and receive SMS messages, but Google Voice does not use the Internet to place calls like Skype. When you initiate a call with Google Voice, the service asks you which phone you want to use for the call and then Google Voice dials that phone and the outbound call simultaneously and completes the call, therefore providing outbound calls over the telephone network.
Phone routing is valuable because with it you can provide one phone number and when someone calls that number, the call will simultaneously ring on any number of phones that you have defined. Google Voice provides a way to define at what times of the day it will route calls to a particular phone. So, for example, if on the weekends you don’t want calls routed to a work phone, you can configure Google Voice so that it will only send calls to your personal phone on the weekend.
Google Voice Locations is an Android application that takes the control a step further by allowing you to define which phones to route calls to based on where you are located. The location is determined by using the GPS inside the Android mobile phone, so that phone needs to be with you in order to determine your location. An example of how you may use this is if you include a home phone number in your Google Voice phones list, Google Voice Locations can tell Google Voice to not ring your mobile phones when you are in your house, and thus preventing you from hearing two or more phones ringing while at home.
Android users will find Google Voice Locations in the Android Market.