What is the meaning of "The selected camera is not compatible with EOS Remote" when connecting Canon DSLR 750D with Apple 6?

It means that the software does not support this model.

Canon (Canon ), is a Japan's world's leading integrated group of production of imaging and information products, specializing in the production of images, optical, medical equipment, semiconductor industrial equipment and office automation products, since its establishment in 1937, after years of unremitting efforts, Canon has globalized its business and expanded into various fields.

Canon's product lineup*** is distributed in three major areas: personal products, office equipment and industrial equipment, with major products including cameras and lenses, digital cameras, printers, copiers, fax machines, scanners, broadcasting equipment, medical equipment and semiconductor production equipment.

Canon is headquartered in Tokyo, Japan, and has four regional sales headquarters in the Americas, Europe, Asia, and Japan, with 200 subsidiaries around the world employing over 100,000 people.On January 20, 2016, the Canonrumors website stated that Canon would release new products in February.