Apple mobile phone settings ~ notification center ~ what does it mean to mark that switch with an icon? Thank you for your answers.

Apple's mobile phone sets the application icon marker switch in the notification center to indicate how many unread messages there are in the application, and the digital marker is displayed in the upper right corner of the application icon. If you want to get unread information, click to enter the application to view it.

IPhone is a series of smart phones developed by Apple, which is equipped with the iOS mobile phone operating system developed by Apple. The first generation of iPhone was released by Steve Jobs, CEO of the company, on June 9, 2007, and officially released on June 29 of the same year.

September 20 13 13, Apple launched the seventh generation products, namely the iPhone5C and iPhone5S, which were officially released on September 20 of the same year. The eighth generation iPhone6 and iPhone 6? Plus was officially released on September 20 10 14. On September 8, 20 16, the iPhone 7 and iPhone 7 Plus were officially unveiled, and the appointment was opened on September 9, and it was officially launched on September 16. 2017 September 13, Apple released three new iPhones, namely, the 4.7-inch iPhone 8, the 5.5-inch iPhone 8 Plus and the 5.8-inch iPhone X..