Second only to Nike in U.S. sports apparel sales, Under Armour is flexing its digital muscles as 62 million people now log on to one of its apps every month. CEO Plank built that “community” by shelling out $710 million this year—the equivalent of the company’s last three years of pre-tax profits—on three fitness apps: MyFitnessPal ($475 million), MapMyFitness ($150 million), and Endomondo (85 million). Plank thinks apps and gadgets will help him compete with Google, Apple, Jawbone, and Fitbit. His rationale is that fitness apps encourage people to work out, leading them to buy more attire. Under Armour’s sales continue to bulk up, with a 20% improvement in the 12 months ended Sept. 30 (compared to 2014), according to S&P CapitalIQ. Because of all the spending, however, profits only inched upward. In three years, the company expects annual sales to double to $7.5 billion.