Following up on last year's question of "What's the carbon footprint of sending a text message?", The Guardian has now asked "What's the carbon footprint of making a mobile phone call?"

Climate change expert Mike Berners-Lee has considered rather more than the earlier article, factoring in phone manufacture and network administration alongside power consumption. His answer is that a minute's mobile-to-mobile call will generate 57g of carbon.

UK telecoms regulator Ofcom has published its Market Data Update for the last quarter of 2009. It says total revenue fell by 2.1% year-on-year across the UK's four largest mobile operators. However, it notes this was the slowest rate of annual decline during 2009.

Total call volumes across the four network operators increased by 6.3% year-on-year to 27.4 billion in Q4 2009, although roaming call volumes were down by 1.5%. The total number of messages sent reached nearly 26 billion in Q4 2009, equivalent to 367 messages per subscriber; significantly higher than the Q4 2008 figure of nearly 20.5 billion or 299 messages per subscriber.

The Organisation for Economic Co-operation and Development says Finland, the Netherlands and Sweden have the lowest prices for mobile phone calls among its 30 member countries.

The highest mobile call charges were according found in Canada, Spain and the USA.

Dr Mark K Smith from ipadio.com joined us for this week’s podcast.

He talks about the recent launch of ipadio, which can turn a telephone call into a live web broadcast and a phone blog.

Mark Windle, head of marketing at OpenCloud, predicts that this year’s reduction in the number of traditional telecoms operators in some countries will provide an opportunity for other operators to innovate and capture market share in 2016.

He says next year will be a year of rapid change for telecoms… whether it’s MVNO disruption, competitive tariff pricing or simply defence from the ‘dark art’ of hacking.

Mark Bridge writes:

The most memorable moments in life often go unrecorded. You don't have your camera in your hands. Your finger is still hovering over the 'pause' button on your audio recorder. Or you were simply too busy experiencing whatever was happening. It's all about the one that got away.

That's where Kapture can help.

Mark Bridge writes:

James Rosewell shows me a colourful roll of paper that's the width of an iPhone but well over three metres long. When I look closer, I can see it's a printed copy of the Wall Street Journal's mobile website. That's a lot of scrolling to do... and a pretty unfriendly user experience for anyone reading the news online. Why does it work so badly?

Iain Graham, James Rosewell and Mark Bridge return to review their mobile industry predictions from last year. Which mergers, partnerships and developments did they forecast correctly... and which didn’t work out as planned?

Later in the programme, the team anticipates some of the topics that will be hitting the headlines during 2016.

Mark Bridge learns about the mobile technology trends at Mobile World Congress 2015 by chatting to James Rosewell of 51Degrees, Dr Kevin Curran from the IEEE and Chris Millington of Doro.

They talk about wearable devices, wireless charging, mobile operating systems and much more... including some of their favourite products from the exhibition.

We're taking a look back at the biggest mobile industry news stories from February 2015, including allegations that the UK's security service tried to breach SIM card security by hacking into one of the world's biggest SIM producers.

We also talk about the planned BT and EE merger, the creation of two new UK virtual networks, some acquisitions in the mobile payment arena and a new Ubuntu smartphone.

In today's programme Mark Bridge talks to Chris Millington, who's Managing Director for Doro UK and Ireland.

They discuss the state of mobile retailing in the UK, the future of wearable devices and - as you might expect - smartphones for seniors.

We're back with a month of mobile industry news, including takeover talks and takeover rumours. O2 and Three are said to be discussing a merger... but is there any truth in the suggestions that BlackBerry could be up for grabs?

We also discuss Apple's record-breaking quarterly figures, the highlights of CES and the launch of Microsoft Windows 10, as well as saying farewell to the current version of Google Glass.