A growing number of consumers are viewing their smartphones as the best tool to save money while staying aware when buying. About six in 10 mobile users say they'll be using their phones for holiday shopping, and retailers are falling all over themselves to offer applications and mobile websites to meet the demand. With smartphones, shoppers can compare prices, store loyalty and gift cards, make wish lists and get discounts at their favorite stores.

Thereby, retailers risk alienating their customers if the apps and mobile websites fail to deliver. According to a study by Gomez, Compuware's unit that studies website performance, over 50% of customers surveyed say they won't return to a mobile site if they've had a poor experience.

Besides, the overall performance expectations are also high as about 60% of people anticipate mobile sites will run as smoothly as or better than sites they visit on their computers, the Gomez study showed. Consumers ranked the performance of mobile sites of the Thanksgiving holiday weekend's 15 largest retailers as "tolerable," compared with the retail websites overall.

Mobile phones offer shoppers the resources of the Web while they're in a store and enable retailers to deliver the most relevant deals. But shoppers can also use them to make purchases with their credit or debit cards, though they could be opening themselves up to identity theft, says John Hering, CEO and co-founder of Lookout Mobile Security. "The mobile device has become the most personal computer and, with that, identity thieves are now beginning to turn their sights to smartphones," he says.

Retailers have long matched rivals' prices, and shoppers search ads in fliers or on the Internet to find the best offers. Now, consumers can discover competitors' prices while in a store, thanks to mobile sites and apps such as PriceGrabber, which more than half a million consumers have downloaded.