Answer first: compare the real display with a screenshot to separate rendering from panel hardware
Flicker and lines can come from display settings, an app or OS rendering issue, or physical display damage. A screenshot test plus low-impact software checks can help separate those paths.
Separate likely causes by symptom
| Symptom | Check | Interpretation |
|---|---|---|
| Issue appears in screenshot | Check app/OS/rendering | Software path first |
| Real screen is bad, screenshot looks normal | Display hardware is more suspect | Hardware path |
| Flicker changes with brightness | Check brightness/adaptive display settings | Possible setting dependency |
| Only one app is affected | Update/restart the app | App-specific issue |
| Started after impact/pressure/liquid | Seek repair | Possible physical damage |
Check one low-impact condition at a time
- 1Restart the phone
- 2Take a screenshot and compare the saved image with the physical display
- 3Check brightness, adaptive brightness, color/display, and power-saving settings
- 4If only one app is affected, update or restart it
- 5Check OS updates
- 6If lines or flashing persist after impact or liquid exposure, move to repair
Avoid changing several conditions at once; retest after each change so the cause remains identifiable.
When to move to repair or official support
- The issue began after a drop, pressure, or liquid exposure
- It persists after restart, updates, and accessory/environment checks
- There is overheating, odor, port damage, battery swelling, or another safety concern
Treat erase/factory reset as a later option only after backups and account recovery paths are confirmed.