Only the brave leave home without the internet in their pockets. Mobile phones now combine high-speed access withentertainment: mobile cameras, video, music, films and information sharing sit alongside serious business services running on devices designed for all kinds of users. The latest smart phones marry voice with text and email, provide easy and fast access into company systems and include personal organisers. Most have GPS and mapping, making it easy to find everything from parking places to restaurants, hotels or tourist sites. A new Nokia phone even includes a compass.

Such multi-functional, high-end smart phones pack the punch of mini-computers. They have gigabit memories, simple menus and connect to broadband 3G networks.

People are beginning to use mobiles to control equipment including video recorders to monitor property or children, and lock doors remotely. In Japan around 4,000 buildings allow mobiles to be used as remote door keys and people can access the internet to monitor video cameras. Phones are even turning into credit cards and supporting internet banking.

Having loaded phones with multiple applications, handset manufacturers are now concentrating on making them easier and more intuitive to use. It is one thing to embed numerous bells and whistles but they will not succeed if people cannot quickly find and use them.

One of the reasons behind the Blackberry’s success is that it is a serious business device providing relatively easy access to corporate services. Although not essentially a business tool, the design triumph of the iPhone has challenged the industry to create simpler, attractive interfaces. Sony Ericsson and Garmin both recently introduced phones with pure touch-screen fronts. Manufacturers have increased screen sizes to make video more appealing and some automatically switch the picture from portrait to landscape when the phone is turned.

Some devices have actual or “virtual” Qwerty keyboards making typing easier. Memos can be handwritten and saved as electronic post-it notes. Downloading and sharing photos and music is easier – content from new Nokia phones can be uploaded to its Ovi service in one click.

“Rather than killer applications we should be talking about killer devices delivering quality of experience,” suggests Andre Mechaly, VP marketing/communications, mobile access division at Alcatel-Lucent. Yet applications translate into revenues and some interesting developments are in the pipeline. Mobile payment promises to speed up paying for goods and services and eliminate the need to remember multiple PINs. Holding handsets within centimetres of Near Field Communication (NFC), point-of-sale terminals enables secure payment for everything from restaurant bills to groceries. Travel, theatre and parking tickets can already be paid for by mobiles which will eventually act as credit, debit and store cards and support internet banking and e-coupons. Underground trains in many major cities including London can already be paid for by holding a mobile within centimetres of a reader.

Unsurprisingly Asia is leading the field. Japanese operator NTT DoCoMo has been running a mobile payment system based on its Felica chip phones for around two years. Approximately five million people use them as credit cards in 300,000 outlets.