It's not a meaningful category. They are all mobile phones, or smartphones if need be to distinguish there. Which practices a monopolistic company can do, but

It's not a meaningful category. They are all mobile phones, or smartphones if need be to distinguish there. Which practices a monopolistic company can do, but is not allowed to, is written clearly in the article: Forcing/Paying other companies to pre-install its proprietary apps. A non-monopolistic company is allowed to do that.