Phone Screen Has Lines
Check vertical or horizontal lines on a phone screen and separate display damage, touch issues, OLED retention, cable faults and software symptoms.
Quick answer
Lines on a phone screen can come from the display panel, an internal connector, impact or liquid damage, graphics output, an app or software. Check whether the line appears during startup and whether a screenshot captures it, then repeat solid-color and touch tests without pressing the display.
Last reviewed: August 2, 2026 · Testing method and editorial policy
Use a screenshot as one clue
If the line is visible in a screenshot on another device, the source may be software, the app or graphics output. If the screenshot is clean but the physical display still shows the line, the screen path is more likely involved.
Check whether it is fixed
A panel or connector symptom often remains in the same position across apps, solid colors and startup screens. A line limited to one image, webpage or app may come from the content or software.
Protect a damaged phone
Do not twist, press or heat the screen. If lines follow an impact, liquid exposure, swelling, flicker or spreading dark areas, stop testing and contact qualified repair support.
How to verify it
- Restart the phone and observe the startup screen.
- Take a screenshot and view it on another display.
- Run solid colors and draw across the touch surface.
- Document fixed lines and seek support if they persist or follow physical damage.