The iPhone is only a precursor to what mobile internet devices will be capable of in the near future, according to a study by ABI Research.

ABI predicts an explosion of mobile internet devices that can be used for browsing the web, listening to music, text messaging, and shooting photo and video. In particular, the study expects that 90 million mobile internet devices and 5 million ultramobile PCs (UMPC) will have been shipped to buyers by 2012.

According to ABI vice president Stan Schatt, these devices will have larger screens than the iPhone and will have a wider variety of web browsing options than Nokia's N800 phone.

"These are going to serve as substitutes for existing portable devices," Schatt says. "These devices could very well play the role of a Swiss Army knife. So, say somebody's going on a trip, and they may take one of these devices that would allow them to watch a movie and also allow them to play a game on the internet."

Because many of these devices would be small and have limited battery power, Schatt says, many of them would save power by being based on Linux instead of Windows.

The most well-known Linux-based platform is currently being developed by Intel, which debuted its plans to enter the nascent mobile internet devices market in April.

"You're going to have devices that cater to certain market segments," says Schatt. "We see, for example, devices catering to Generation Y social networkers. These devices would be highly stylised, they would have webcams, they would be optimised for texting and [instant messaging], and they would have some phone functionality. They would allow you to be connected all time, enable you to connect via video, text and voice."

The study notes that the potential for mobile internet devices isn't only in entertainment and communications, but also in the medical field, where they could be used as devices that monitor crucial health indicators and send that information through a wireless signal to doctors and family members. Schatt says he also expects mobile internet devices to be developed that specialise in performing very specific tasks for people who work in isolated conditions. "Say you have a petroleum field engineer out in middle of nowhere, and he has to be connected to the Internet, and there's a very specific application he needs to run," he says. "These devices would be ideal for that sort of work."

While Schatt sees a very bright future for mobile internet devices, he thinks the future of UMPCs, such as the OQO Model 01+ and the FlipStart, is somewhat cloudier. The two big problems with UMPCs, he says, are that their processors still are taking up too much battery power, and that they haven't done enough to differentiate themselves from laptops.

"It's going to take two or three years before they have a low-power processor that has enough juice to run one of these machines all day," Schatt says.