O2 has followed the lead of other mobile companies in announcing a flat-rate charge for data on its mobile network.

The operator's Bolt On offering caps data charges at £7.50 a month within a 200MB limit. The company also has a 3GB data rate set at £30 per month.

Sally Cowdry, director of marketing at O2, said: "O2 has a whole range of devices which provide a great mobile internet experience such as the Xda Orbit, BlackBerry and, of course, the iPhone.

"We are now offering unlimited Bolt Ons to help our customers do what they want without worrying about the bill."

The company is also offering a special BlackBerry deal at £10 per month, also capped at 200MB.