While there were portable digital music players before the iPod, Apple's clean, simple design was the first to capture customers' imagination. "Once you've staked out ownership of the sector in the mind of the consumer, it's hard for a competitor to shake you loose," says Laura Ries, president of Ries & Ries, a marketing strategy firm based in Atlanta. An innovative product that resonates with consumers markets itself -- the new iPhone is simply Apple's latest.