In 2005, when began planning the he had a choice to either “shrink the Mac, which would be an epic feat of engineering, or enlarge the iPod”. Jobs favored the former approach but pitted the and and , respectively, against each other in an internal competition, with Forstall winning by creating the iPhone OS. The decision enabled the success of the iPhone as a platform for third-party developers: using a well-known desktop operating system as its basis allowed the many third-party Mac developers to write software for the iPhone with minimal retraining. Forstall was also responsible for creating a for programmers to build iPhone apps, as well as an within
The iOS is based upon using gestures such as . Interface control elements include sliders, switches, and buttons. command) or rotating it in three dimensions (one common result is switching between portrait and landscape mode). Various described in functions enable users with vision and hearing disabilities to properly use iOS.
iOS devices boot to the homescreen, the primary navigation and information “hub” on iOS devices, analogous to the desktop found on personal computers. iOS homescreens are typically made up of app icons and widgets; app icons launch the associated app, whereas widgets display live, auto-updating content, such as a weather forecast, the user’s email inbox, or a directly on the homescreen.
Along the top of the screen is a status bar, showing information about the device and its connectivity. The status bar itself contains two elements, the Control Center and the Notification Center. The Control Center can be “pulled” down from the top right of the notch, on the new iPhones, giving access to various toggles to manage the device more quickly without having to open the Settings. It is possible to manage brightness, volume, wireless connections, music player, etc.
Instead, scrolling from the top left to the bottom will open the Notification Center, which in the latest versions of iOS is very similar to the lockscreen. It displays notifications in chronological order and groups them by application. From the notifications of some apps it is possible to interact directly, for example by replying a message directly from it. Notifications are sent in two modes, the important notifications that are displayed on the lock screen and signaled by a distinctive sound, accompanied by a warning banner and the app badge icon, and the secondary mode where they are displayed in the Notification Center, but they are not shown on the lock screen, nor are they indicated by warning banners, badge icons or sounds
It is possible to choose if notifications from an app can be shown on the lock screen, Notification Center, banner, or all three; whether the banner should be temporary or permanent; activate or deactivate the sound; choose whether to group by app or not and whether to show previews when locked. It is possible to turn off unwanted app notifications. Older notifications are automatically deleted after a few days.
A homescreen may be made up of several pages, between which the user can swipe back and forth, one of the ways to do this is to hold down on the “dots” shown on each page and swipe left or right.
To the right of the last page, the App Library lists and categorizes apps installed on the device. Apps within each category are arranged based on the frequency of their usage. In addition to a category for suggested apps, a “recent” category lists apps recently installed alongside App Clips recently accessed. Users can search for the app they want or browse them in alphabetical order.
iOS also integrates seamlessly with other programming frameworks and technologies, such as Apple Pay, HomeKit, HealthKit, and ResearchKit.
On iOS, the main page button is usually located at the top right. To go back in an application there is almost always a “back” button.