The argument for third- and fourth-generation (3G and 4G) cellular services is simple. Consumers are increasingly relying on their handheld devices to send text and photos, surf the Internet, and even take and share video clips. It follows that consumers would be interested in watching television programs, music videos, and more on their handheld devices. When the next generation of services combines with location-based services, however, there is the potential for services that range from irksome to dangerous.

In this age of "social networking" through websites like MySpace and YouTube, what some have dubbed personal-area social networking (PASN) is growing in popularity. Essentially, PASN will enhance existing social-networking applications by allowing users to easily find and connect with one another. Of course, such connections depend on the user's security and auto-connect settings. One can assume that someone could only discover their location if they were on a sort of "buddy list." When it comes to children and trusting adults, however, a person who is labeled a "buddy" could turn out to be nothing of the sort.

For example, say a teen regularly competes against other people online. Some of those people—generally teenagers—live in the same area. If the teen adds these people to his or her PASN "buddy list," they could meet up. The potential risks are obvious.

In the near future, this automatic-discovery feature is expected to be realized through ultrawideband (UWB) technology. Thankfully, UWB only permits handset owners to connect with applications or other handsets within 10 meters. The chances of someone on the consumer's "buddy list" actually being within 30 feet at a given location, such as a shopping mall, are rather rare. In the case of the teenage gamer, most of the alerts about a friend in the area would undoubtedly be other teenagers at school-related functions.

Location-based services also are predicted to spur mobile advertising. Specifically, companies are expected to market to the consumer's phone based on the consumer's location. The messages will change with geography. For example, imagine walking down a city street. An advertisement for a nearby restaurant offers 20 percent off of any main course. Five minutes later, a "buy one T-shirt, get one half off" offer comes in for the clothing store that is just up the block.

Generally, location-based services will enable a number of very helpful applications. Yet they also invite some potential dangers. Even if they do not pose a threat, these applications may persistently interrupt the consumer's life simply because of his or her location. Eventually, some of us may be left wondering why we can no longer run an errand in peace.