July 2005

From the Lab: Information Technology

Continued from page 2

By Monya Baker (editor)

Timing Text
Mobile messaging on cue

Context: Some text messages, like birthday wishes or driving directions, make sense only in particular contexts. But cell phones send messages immediately, not when they are most timely. Younghee Jung, Per Persson, and Jan Blom of Nokia have now designed cell-phone software that lets senders dictate when and where their text messages should be delivered.

Methods and Results: Cell phones already track what time it is, where they are, and who has called recently. Jung and colleagues wrote software that monitors this information and withholds messages until certain delivery conditions are met. They designed a user interface that lets senders choose conditions such as time of day or a recipient's location. Finally, they loaded the software onto phones, gave them to seven Finnish teens, and monitored their use over several weeks.

More than 10 percent of all sent messages used this "context-enhanced" delivery. Just over half of these were triggered by the recipient's location -- in, say, the vicinity of a common rendezvous point. Most of the rest specified when a message should be delivered, and many were timed to reach friends when they were in between known engagements.

Why It Matters: Context-specific delivery could change the way people use cell phones. However, the change could be as much a curse as a benefit. Although the teens' biggest complaint was that they couldn't be sure friends received their messages, the researchers haven't yet identified a way to verify delivery that protects the recipient's privacy. If a phone sends a confirmation when a message is read, it will also reveal where the recipient is. Vendors might also be tempted to send messages that would be delivered as users neared their shops' locations, creating a boom in text-message spam.

Source: Jung, Y., et al. 2005. DeDe: design and evaluation of a context-enhanced mobile messaging system. Paper presented at Conference on Human Factors in Computing Systems. April 2-7. Portland, OR.