Sure, we live in networked times, but the phone still plays a big role. In about a dozen digits, you can reach anyone in the world with a phone. Now there's also a way to get at much of the metadata that goes along with it, such as where a phone number is likely based. That and more is being made available for free via the Cloudvox Digits API (our Cloudvox API profile).
Given a ten digit U.S. telephone number, the API responds back with the state and, if available, city where the number is likely to belong. Also included is the carrier, which can help determine the classification of a phone--is it a land line, VOIP or mobile phone?
For mobile phones the carrier can be especially interesting. Methods of accessing wireless features, such as sending a text message through an email address, can differ by provider. There are many sites that will send the text for you, but you need to know your friend's provider. With the digits API, those same services could possibly automate the process, so that you only need to know your friend's number.
As for the location, it's important to note that this API uses the phone number, not a geolocation method through the carrier. There are alternate methods for determining the location behind a phone number. But it involves a little extra work, as well. For example, you can search for a phone number and usually determine where it's from within a few tries. But that doesn't get the same data into your applications.
Along with the API, Cloudvox has a bookmarklet that uses the API to bring the answer to users while searching. This also shows off some of the functionality available via the API, but you'll want the full Cloudvox API docs when it comes to incorporating it into your application. It's free and does not require a signup or API key.
And how's the accuracy of the data? Certainly it's not 100%, but it gets close. For my office phone, a VOIP number, the location is listed as a suburb outside of the city where I live. Other services may have better data, but Troy Davis, director of Cloudvox Services, tells us they cost money and aren't API-oriented. Cloudvox goes after what Davis believes is the mainstream use case: "as good as you can get without a per-use fee."
Of course, there's an elephant in the room with respect to data accuracy. Area codes no longer have as much to do with where the phone's owner lives. People tend not to change their mobile numbers despite a move across the country. And VOIP providers will sell you a number with any area code you want, no matter where you live.
Even with that fact, there is still a lot of information behind a phone number and this can be a valuable new service for developers.
Disclosure: Cloudvox is a sponsor of ProgrammableWeb