The iPhone is one of the two largest smartphone platforms in the world alongside Android, forming a large part of the luxury market. The iPhone has generated large profits for Apple, making it one of the world’s most valuable publicly traded companies. The first-generation iPhone was described as “revolutionary” and a “game-changer” for the mobile phone industry and subsequent models have also garnered praise. The iPhone has been credited with popularizing the smartphone and slate form factor, and with creating a large market for smartphone apps.