More and more people are using cell phones for more than calling, embracing data services like text messaging and ring tones — and devices also are improving. Advertisers, meanwhile, are starting to experiment with mobile ads. With a boom in GPS devices and location services like maps and child tracking, it’s only natural that advertisers, too, will want to take advantage of location information.

Companies are also developing ways to share profiles with marketers while stripping out sensitive information like names. The challenge will be getting consumers at the right state of mind. You might appreciate that restaurant discount when you’re hungry but not if you’ve just finished lunch. The mantra, for now, is to avoid the type of backlash that online hangout Facebook recently faced when it enlisted users as endorsers of movies and other products, initially without them necessarily realising it.

“We know this is a great opportunity for targeting, but we don’t want to blow it by overdoing it,” said Eswar Priyadarshan, chief technical officer for Quattro Wireless Inc, a mobile ad distributor.