HD Voice can apparently reduce the hisses and fuzz that often make mobile phone conversations difficult to make out. It has been launched on the network this week, with Orange making a point of focusing on raising the level of basic calls rather than on developing smartphone apps.

The company claims that the new system will be most noticeable for people who often make phone calls to or from trains or noisy workplaces. It will also eliminate the perceived distance between callers, enhancing the transfer of emotion in people's voices.

Mobile phone technology expert, Jonathan Leggett, said HD Voice showed Orange's commitment to the primary function of mobile phones.

"We don’t expect Orange’s HD Voice technology to sway young smartphone users," he said.

"Improving the calling experience, however, will appeal to less tech hungry consumers who use their handsets predominantly for making calls and texting."

The service is on offer with mid-range and entry-level mobiles, such as the Nokia 5230 and Samsung Omnia Pro. HD Voice will only initially work on the Orange 3G network between HD-enabled handsets.

The i-migo is a keyring-sized stick that can be connected via Bluetooth to a mobile phone and will let off an alarm if the phone gets more than 30 feet away.

The device can also lock the phone so that no-one else can use it and will even notify your phone network that they should start tracking it using GPS.

Crucially, if you don't get your phone back, the device stores all of your data on the phone – numbers, contacts, photos – and can replicate them on to your new handset.

The device already comes with high praise, having won the 2009 UK Design Council Mobile Phone Security Challenge. The government-supported challenge tasked designers to come up with ways of securing phones and making them less desirable to thieves.

Mike Midge, director of sales and business development at Data Transfer & Communications, the company behind the device, said there was clear need for something like the i-migo and they already had patents on the technology in the US, Europe and China.

He said they wanted to penetrate the Chinese market, but were aware of the risk of piracy.

"We feel there is a very clear need for it in the China market, but the simplicity and straightforwardness of the intellectual property means you could easily replace individual functions, and that is a huge challenge," he said.

Sony Ericsson's Elm handest emerged as the most eco-friendly phone currently available, after being judged on factors including the corporate responsibility and processes of the manufacturer, component materials – including packaging – and the costs of both running and disposing of the phone.

Glaring omissions from the list were Apple and RIM, the companies behid the iPhone and BlackBerry. The computer giant choose instead to rate its models according to its own environmental policies, while RIM pledged to join the scheme next year.

An O2 representative said they hoped the scheme would establish an industry-wide standard measure of a phone's sustainability.

The scheme awards phones a ranking on a scale up to five (including decimal points) – represented on packaging with a rainbow icon. The Sony Ericsson Elm achieved an Eco rating of 4.3 out of 5, while the worst performing phone was the destructively-named LG Etna, which scored just 2.7.

Most of the major manufacturers chose to take part in the scheme, including HTC, LG, Nokia, Palm, Samsung and Sony Ericsson – which covers 93 per cent of the handsets sold by O2.

The Eco ratings can now be found on O2's website or in their high street stores.

The computer scientist behind the project, Weng Castillo, said it was a very effective way of getting very important information across.

"Every farming household has a cellphone, so it should be easy to reach most farmers," she said, having noticed that phones had much greater presence than computers and heard the frequent statistics showing that people in the Philippines text more frequently than any other nationality.

The information dispensed will be specific to the terrain and the genus of rice, isolating where each farmer is, assessing the factors affecting the growth of rice there and advising accordingly.

Ms Weng said, "We've been doing research for a long time, and we found that field-specific advice could increase yields. Even rice plants that are adjacent to each other have different requirements for fertiliser."

She said sending the information out in text message made it digestible to farmers who, otherwise, would not have the scientific abilities to understand it.

Farmers will phone a central number, answer a series of simple voice-activated questions about the conditions of their field, and within a few minutes receive a reply. It will detail the amount of rice needed to be sown, the type of fertiliser needed and when it should be applied.

The scientists at the University of Washington (UW) in Seattle hope to effectively transmit American Sign Language via compressed video over a 3G cellular network, without the users requiring the faster and more expensive 4G network.

The engineers have so far been able to increase image quality around faces and hands used in ASL, while still delivering intelligible sign language via video at speeds of 30 Kbit/sec.

A three-week initial trial of the programme – tentatively called MobileASL – on older phones equipped with cameras for video chat, is coming to an end. The handsets use software that can also work on a range of smartphones and other mobile devices.

They enlisted the help of 11 students in a UW summer academy for people who are deaf or hard of hearing who are also interested in computing careers. The group made 200 calls using the software, each lasting around nine seconds, with generally positive results.

The field study was headed by Jessica Tran, a doctoral student in electrical engineering. A larger test on MobileASL is planned for the winter.

Supermarket giant, Tesco, launched the SIM-only deal this week on a rolling tariff, aiming it squarely at teenagers. They aim to capitalise on the overwhelming preference of teenagers to text rather than make calls.

Until this deal, however, many have been bound to pay-as-you-go phones unless their parents were willing to sign them up for a monthly contract.

Tesco's chief executive for its mobile and telecoms divisions, Lance Batchelor, said, “This deal is ideal for a younger market or any text addict out there who doesn’t want to have to fork out a large amount each month but still wants to use their mobile to their heart's content."

"We've seen a big increase in SIM-only mobile tariffs as savvy spenders hang on to their handsets and shop around for the best tariffs available."

The supermarket's pricing strategy was devised after a careful examination of the texting and calling habits of different age groups. Research by the company discovered that nearly a third of 16- to 24-year-olds spent more than £30 per month on their mobile phone bills, largely due to the high number of text messages they sent.

Many users have lodged official complaints with Vodafone, after loading an update on the Android-operated handset that they cannot remove and which some people say is leading them to utterly inappropriate websites.

The customers had been waiting for the new Android 2.2 update and are deeply unsatisfied with the development, which also includes a music shop which, again, cannot be removed.

Vodafone spokesman has responded to the criticism, through one of the company's official online forums. He said it was all part of the company's optimisation progress.

"We customise phone software to optimise customers' experience of the device on the Vodafone network and to enable access to our services," he said.

"At a basic level, this can involve ensuring services like MMS, voicemail and data connections are set correctly. In other instances, our customisation is more extensive such as the preloading of services (People, My Web, 360 Shop, etc), but this varies from device to device."

The 2.2 system – known as ‘Froyo’ – has been rolled out to users of Google’s Nexus One handset but the update schedule for other devices is in the hands of individual manufacturers and networks.

Manufacturers, Research in Motion (RIM) revealed the Torch 9800 at a glittering event in New York this week, displaying a model that combines both a touchscreen and a key pad. RIM CEO Mike Lazaridis said every effort had gone in to making this phone as close to perfect as possible.

"We spent a lot of time on the details – how the applications interact, how the features interact," he said, hoping to combine the brand's corporate popularity with consumer appeal.

"Following extensive research and development to address consumer needs and wants, we are delivering a communications, browsing and multimedia experience that we think users will love, and we are thrilled to debut BlackBerry 6 on the amazing new BlackBerry Torch smartphone."

Features on the new device include a 5-megapixel camera with flash, autofocus and geo-tagging feature, a large 3.2-inch capacitive touchscreen and a 624MHz processor.

Unlike its predecessors that only catered to the needs of corporate users, BlackBerry 6 offers integrated connectivity with social networking sites like Twitter, MySpace and Facebook and hence is likely to appeal to a broader customer base.

The UAE has banned the use of email, instant-messaging and web-browsing services on the handsets, following a long-running security spat with the device's Canadian maker, RIM.

Saudi Arabia's state-controlled Saudi Telecom revealed to the Financial Times that they too were looking into banning BlackBerry messenger services.

The bans comes as concerns from the Gulf states over encryption technology used by BlackBerry devices reach a peak. The technology for the network functions means data is exported offshore, making it very difficult for it to be monitored by outside bodies, such as the UAE state communications body. India has also expressed concerns about the way that BlackBerry devices operate.

The UAE's Telecommunications Regulatory Authority (TRA) stressed that the decision was not about censorship but about regulatory compliance.

"We are not asking for RIM to do anything that is not apparently being done in developed nations or so-called open countries around the world," said Mohammed al-Ghanim, TRA director-general.

The UAE has tried to monitor BlackBerry users previously, with local operator Etisalat telling BlackBerry users a year ago to install upgrades that turned out to be spyware.

Information compiled by Gartner shows that the market has been buoyed by new carriers and new manufacturers, increasing competition and pushing down call rates and handset costs.

The figures mean the India now accounts for 10 per cent of all global mobile phone sales, which has led to a surge in manufacturers that means the market now offers a choice of more than 50 different brands.

Anshul Gupta, principal research analyst at Gartner, said the market was now progressing into the next phase.

"Cellular phone penetration in India stood at 45 per cent in 2009, and the market is now entering into a second phase of growth, with replacement sales increasing from 45 per cent in 2009 to 50 per cent of total sales in 2010," he said.

"The move to high-speed 3G networks is bringing in more challenges in terms of innovation and keeping up with fast changing consumer demand. Shortening product life cycle times and declining sales of voice-centric devices will bring changes to the market during the next five years."