In a bid to increase the amount of data its customers consume, Three UK launched its so-called “Facebook Phone” today, which Britain’s smallest carrier and its handset partner INQ Mobile are calling the world’s first social mobile phone.

While the handset—the INQ1—does give consumers one-click access to Facebook and live updates pushed direct to the front screen of the handset, the real story is the pricing of the phone. The phone is free on an 18-month contract tariff of £15 a month ($22), which includes unlimited free Facebook, Skype, Windows Live Messenger and up to 1 GB of web access, unlimited emails, unlimited texting, and unlimited calls to other Three customers, plus 75 minutes of talk time to other networks. For an additional £5 ($7) more a month, talk time to other networks bumps up to 200 minutes. For pre-paid users the phone costs £79.99 ($119), plus they will need to pay at least £5 ($7) a month on internet access.

Three UK CEO Kevin Russell said the rationale behind the phone and the pricing was to “open the market up,” and to increase the amount of data customers used. The “explosion of the mobile internet” was “not going to happen,” he noted at this morning’s press conference, as long as data-oriented handsets such as the iPhone, Blackberry Bold, and the G1, were priced as high as they were. Of course, the INQ1 doesn’t do as much as these other phones. The upstart handset maker’s CEO Frank Meehan concedes there’s no big app store for it, or endless applications available to consumers. Plus, should the phone prove popular, there’s not much to stop other handset makers from offering their own versions.