Black Line at the Bottom of Smartphone Screens: Design or Feature?

New Delhi: Modern smartphones, smartwatches, laptops, and tablets increasingly rely on touchscreen technology, and a small yet significant change has become standard—the black line at the bottom of the screen. While some users may think it’s purely a design element, this line is actually a functional navigation tool that replaces the traditional physical home button.

What is the Black Line?

According to UI/UX expert Ljubomir Bardzic, nearly all modern smartphones feature this line at the bottom of the display. It is commonly found on iPhones and almost all Android devices from major brands like Google and Samsung. The black line serves as a home indicator bar, gesture bar, or navigation bar. On phones with a physical home button, this feature essentially performs the same functions, adapted for gesture-based navigation.

How Does It Work?

The black line allows users to switch between apps, go to the home screen, and minimize applications with simple gestures:

• Swipe up: Return to the home screen.
• Swipe up and hold: View all open apps and switch between them.
• Swipe left or right on the line: Quickly move between recent apps.

As smartphone screens grew larger and bezels shrank, physical home buttons were removed. The black line now serves as a central control tool, making multitasking faster and smoother.

Differences Between iPhone and Android

While the feature works similarly across devices, gesture controls differ slightly:

• On Android, users can swipe from any edge to go back.
• On iOS, a swipe from the left edge to the right performs the back action.

Overall, this small black line improves usability, multitasking, and overall navigation, making smartphones more intuitive and user-friendly.