Because each channel helps to drive sales through the other, brands in China find that online to offline (O2O) marketing is particularly effective. Mobile is a key aspect in how retail firms in China are successfully blending consumers' online and offline (O2O) journeys. Shoppers' lives now revolve around their mobile devices. One of the hottest subjects in marketing in recent years has been O2O, which stands for Online to Offline (or, occasionally, Offline to Online). It has been dubbed the industry's stupidest acronym by Tech in Asia and recognized by TechCrunch as a trillion-dollar opportunity. O2O in China has been expanding quickly and is now a major marketing trend, despite some businesspeople disagreeing over how the phrase should be used.