Bored with chatting, sending text messages, and playing games on your cellphone to pass the time? Try watching TV. Thousands of cellphone owners in Europe and North America are doing just that, using services that stream content to their handsets over high-speed, packet-based cellular networks. And millions more could soon join the fray with the launch of an alternative television-broadcast technology.

This reporter tested the streamed service in Germany and viewed a demonstration of the emerging broadcast service at the CeBit 2005 trade show in Hannover, Germany, in March. The verdict: if you're hooked on TV, both services are great for watching news, sports, and quickly digestible entertainment programs, while you're in transit. But watching an hour-long TV program or a movie on a small screen is hard on the eyes, not to mention the wallet if you're buying the video stream from your mobile service provider.

Numerous cellphone operators in Europe and North America are now streaming mobile TV services over their new third-generation (3G) mobile broadband networks. One of the first to roll out the service is the German subsidiary in Dusseldorf of Britain's Vodafone Group PLC, Europe's largest mobile-phone company. After introducing it with a three-month free promotional offer earlier this year, the operator now gives two free hours and then charges 3 euros per hour as part of a monthly mobile TV subscription fee, which, depending on the number of minutes, ranges from 20 to 95 euros.

In North America, too, several cellphone companies now offer streamed TV services over their high-speed networks, including Sprint and Cingular Wireless, in the United States, and Rogers Wireless and Bell Mobility, in Canada. And with an eye to what it views as a potentially lucrative market, cellular equipment manufacturer Qualcomm Inc., in San Diego, is working on its own proprietary streaming technology, called MediaFLO (forward link only). One of the key features of this multicasting technology is that it requires about half as many base stations as in a regular cellular network.

But just as streamed mobile TV services begin to spread, a potential competitor is lurking in the wings. Broadcast technology has one big technical advantage over streaming: one TV tower can beam signals to thousands of handsets simultaneously at far less cost than streaming technology, which requires mobile providers to increase network capacity in high-usage areas like train stations.