Apple is an American multinational technology company that designs, develops, and sells consumer electronics, computer software, and online services. Headquartered in Cupertino, California, Apple is considered to be one of the Big Four technology companies, ranking No. 3 in the 2019 Fortune 500 list of the largest United States corporations by total revenue. In 2006, Apple partnered with Nike to release Nike+, an activity monitoring platform consisting of an iPod, a wireless chip, and Nike shoes. With their expertise in electronics, the company's main patent activity is in the Applications and Devices categories of the Smart Footwear sector.