Yesterday the dominating computer interface was the desktop workstation. Today (or, depending on where in the world you live, early tomorrow morning at the latest) the dominating computer interface is the mobile phone. In Japan and other parts of Asia, more people already use their phones to access the Internet than use a PC. As the capacity of mobile terminals and networks continues to increase, the rest of the world will follow.
Unfortunately, the accepted wisdom from decades of research on interfaces for stationary computers simply does not hold for mobile devices. You will even hear HCI researchers and UI designers complaining that mobile devices are too small and "limited" to permit anything interesting. But the real difference has nothing to do with size. Instead it comes down to the fact that what we do with mobile computers and the situations in which we use them are fundamentally different from what we do with the desktop.
Mobile devices follow us through the day, which means that they are used in many shifting rolesthe user may be an employee one minute, trying to secure an important business deal, and a mother the next, making plans for picking up the kids after school. They facilitate ad hoc meetings, which may be both face-to-face and screen-to-screen-you could be chatting online with someone miles away while at the same time trading pictures with the person sitting next to you. Mobile applications have to migrate to many different devices, so that what works on a low-resolution phone screen when you are jogging also works on a tablet PC at the kitchen table. And mobile services are highly dependent on network access, which can shift dramatically depending on whether you are in a café with a high-speed WLAN or in a forest with patchy GSM coverage.
For the past three years, I worked on a project that took these challenges as a starting point to explore the mobile services of the future. Mobile Life was funded by the Swedish Foundation for Strategic Research and was a collaboration between the Future Applications Lab at the Viktoria Institute, the Interaction Lab at the Swedish Institute of Computer Science, the Involve Group at Stockholm University, and the Mobility Studio at the Interactive Institute. The goal was to investigate mobile services that, rather than just being smaller versions of desktop applications, take advantage of the fact that they are inherently mobile.
Many of the mobile services that were created in the project were based on local interaction. For instance, MobiTip from the Interaction Lab lets you share "tips" with other users in the vicinity through a Bluetooth connection. If you find something interesting, say a restaurant that serves particularly good Chinese food, you can enter this into the system as a "tip." Since your phone continuously exchanges "tips" with other users in the local area, another user might come upon your tip when looking for a good restaurant. An advantage of the MobiTip system compared with other similar recommender systems is that it requires no infrastructure and runs on commercially available devices, and therefore it was possible to release it for testing in a local shopping mall.
Another example of local interaction is the Future Application Lab's Push!Music. What would happen if the songs on your iPod had a mind of their own? In Push!Music, all MP3 files are "media agents" that observe the music-listening behavior of the user and other people in the vicinity. The songs are free to move between devices that are connected in a wireless network, which means that a song can "jump" from one player to another, where it thinks it would be appreciated. For instance, after taking the bus to work, you might discover that several new songs have appeared on your player-and if the algorithm is good enough, chances are that you will even like them! The project raises many questions of security and intellectual property, and to be viable it will also need a robust payment model, either as a subscription service or using one of several emerging peer-to-peer payment systems.
In face-to-face interaction we can use a multitude of means to express feelings and attitudes, such as facial expression, body posture, and tone of voice. An SMS message on a mobile phone, on the other hand, has to be composed using a keypad, can only contain 160 characters, and in general does a very bad job of catching the nuances of human communication. The eMoto project by the Involve group extends the possibilities of mobile messaging by adding an emotional component. By shaking, squeezing, and otherwise mistreating the phone's stylus after you have written a message, you generate a colorful background pattern that expresses the emotion you want to put across. The stylus contains sensors to catch movement and pressure, and the interaction model is based on a psychological model of emotion as well as the emotional value of colors and shapes.
Those who still worry about the "limited" interaction possibilities of mobile devices should note that all the applications mentioned above could be used on a standard mobile phone today (with small modifications). Yet at the same time they drastically expand the interaction parameters of mobile devices by taking advantage of local interaction, observations of the user's behavior, physical input, and so on. Although the computers we interact with in the future may look like the mobile phones of today, they should be much more than that. Only when interaction designers and researchers acknowledge this will they make applications and services that are not just mobile computers, but a natural part of mobile life.
The Mobile Life project
Mobile Life brochure
Lars Erik Holmquist
About the Author:
Lars Erik Holmquist is the leader of the Future Applications Lab at the Viktoria Institute in Goteburg, Sweden. He is interested in innovative interactive technology, including tangible interfaces, informative art, mobile media, and autonomous systems. He was general chair of UbiComp 2002, the international conference on ubiquitous computing, and is an associate editor of the journal Personal and Ubiquitous Computing.
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