Interest in the companies that make wearable technology is heating up as more consumers use their devices.

The shoemaker Adidas announced on Wednesday that it had acquired all outstanding shares of Runtastic, a European maker of fitness apps and wearable activity trackers, in a deal that valued Runtastic at 220 million euros, or about $239 million.

The deal comes after a successful initial public offering in June of Fitbit, which makes wristbands that measure heart rate, pulse and other fitness metrics. Shares of Fitbit made their debut at $20 and have since soared more than 150 percent. They were trading on Wednesday afternoon above $50.

Based in Austria, Runtastic makes health and fitness apps and wearable tracking devices and counts 70 million registered users. With Runtastic, Adidas can better compete with rivals like Under Armour and Nike, which began offering the popular FuelBand activity tracker in 2012.

The global market for wearable devices is expected to grow to 72.1 million units this year, from 26.4 million in 2014, according to a report from the research firm IDC.

Adidas bought the privately owned Runtastic from its majority shareholder, the digital publishing house Axel Springer, and other investors, including the founders of Runtastic.

“This investment will add considerable value on our journey to deliver new world-class sports experiences,” Herbert Hainer, chief executive of the Adidas, said in a statement. “In addition, it offers the opportunity to grow a highly engaged athlete user base and leverage the power of our broad product portfolio.”

Adidas, which is based in Herzogenaurach, Germany, employs more than 53,000 people worldwide and reported sales of €14.5 billion in 2014.

Deutsche Bank advised Adidas, and the law firms Ashurst and Schoenherr served as legal counsel. Allen & Company advised Runtastic, and Milbank Tweed Hadley & McCloy and 42law served as legal counsel.