Mark Bridge writes:

This week has been dominated by the media frenzy that is Mobile World Congress. James Rosewell and I were at MWC for all four days… but even a podcast every day wasn't enough to include all the news, so expect more reports from us next week.

Research In Motion and Telefonica have announced plans to introduce integrated carrier billing to BlackBerry App World. This will allow Telefonica customers around the world to purchase apps from BlackBerry App World and charge them to their monthly bill.

Customers will also be able to add in-app purchases of digital goods to their monthly bill.

Orange UK has launched a contactless prepaid MasterCard card called Orange Cash. The card, which costs £5, can be preloaded with cash and used at contactless or conventional retailers in the UK and abroad.

It's been developed for Orange by prepaid services company PrePay Solutions.

Acer - currently claiming the world no.2 spot for PC and notebook sales - has revealed new tablet devices and a new smartphone this week.

The Acer ICONIA SMART promises a 4.8-inch 1024x480 widescreen and an 8-megapixel camera. The device will run Android 2.3 Gingerbread on a Qualcomm 1GHz processor. UK availability is expected from May 2011.

MobiWire - formerly known as Sagem Wireless - has unveiled a portfolio of secure business phones with embedded security for voice, SMS, data and on-device encryption. There's a feature phone with a proprietary OS and an Android-powered smartphone as well. The devices have been co-developed with secure communications specialists ERCOM following a partnership announced last year.

Control of the phone's security is managed by a company IT department, not by the user. The built-in security cannot be removed from the device or tampered with.