The UK arm of T-Mobile has introduced a ‘pay once’ model for the Blackberry pearl in a bid to drive uptake of data services among prepay users.

Under the deal, customers pay £179.99 for the BlackBerry Pearl 8110 and receive one year’s unlimited email and internet access bundled with the handset.

Customers who take up the offer will be required to top up their credit as usual to make voice calls and send text messages.

The BlackBerry Pearl 8110 features a QWERTY keyboard, two megapixel camera, GPS, and preloaded applications including Facebook, MySpace and Flickr.

Last week, UK market challenger 3 moved to shake up the market by embracing the open network model, announcing plans to allow users free Skype to Skype calls without having to pay data charges.

From May 1st, there will be no data charges or top up fees for either contract or prepay customers who use Skype on 3’s UK network. Anyone with a 3 Skype-enabled handset will be able to buy a 3 SIM and talk as much as they want to other Skype users without ever having to pay a penny.

Then over the summer, 3 will expand its offering to include anyone with a 3 SIM and an unlocked handset, regardless of whether 3 supplied the device or not. The free usage allowance also extends to Skype’s instant messaging (IM) service.