The Screen Shifting Vector
To mitigate the difficulty of using large-screen iPhones with a single hand, Apple introduced a feature known as Reachability. By default, swiping down on the bottom edge of the screen (or lightly double-tapping the Home button on older models) forcefully shifts the entire user interface halfway down the display, allowing you to reach the top icons. However, for users with larger hands, or those playing fast-paced games, this gesture is frequently triggered by accident, violently yanking the application down and severely disrupting the experience.
How to Disable Reachability
You can instruct the iOS operating system to completely ignore this gesture, ensuring the interface remains permanently anchored to the top of the screen.
1. Open the Settings app on your iPhone.
2. Scroll down and tap on Accessibility.
3. Under the Physical and Motor section, tap on Touch.
4. Locate the toggle switch labelled Reachability near the top of the menu.
5. Tap the toggle to switch it to the Off position (the switch will turn grey).
Once disabled, swiping downwards on the bottom edge of the screen will no longer trigger the interface shift, eliminating all accidental disruptions while typing or playing games.