How to use the screen check
- Raise the screen brightness and press "Check in fullscreen".
- Click through white, black, gray, colored screens and the grid pattern while tilting the screen in different directions.
- Find where fingerprints, oil, scratches and dust are, clean, and check again with the same patterns.
How the oleophobic coating works and how to care for a phone screen
A smartphone screen usually has a very thin coating on top of the strengthened glass that keeps oil and fingerprints from sticking. It is called an oleophobic coating, and because it repels oil, fingerprints stick less and wipe off more easily. The coating is extremely thin, so it can wear down gradually as friction builds up over time, and when it wears the screen picks up fingerprints more readily and can feel sticky.
How visible fingerprints and oil marks are varies greatly with background and light. On a bright, even white screen they show as dark smudges, and on a dark screen as reflections. Regular patterns such as grids and stripes help tiny surface flaws show up as bends in the lines. That is why looking at several patterns in turn is effective for checking.
Care for a long-lasting screen and the check before applying a protector
Wiping the screen often with a dry microfiber cloth is the basic care. Cleaners with high alcohol content and rough materials can damage the coating, so check the device maker's guidance. Turning the device off before wiping makes smudges easier to see and prevents accidental touches. Rubbing with sand or dust on the screen can scratch it, so brush it off first.
Before putting on a screen protector, remove as much dust and oil from the screen as possible to reduce bubbles. Switch between the white and black screens of this tool to confirm no dust is left, and check again after cleaning. After applying the protector you can use the same method to look for bubbles or foreign matter.
Tips for checking
- Raise brightness to maximum and check in a dim place.
- Tilt the screen so the light reflects at an angle.
- Check the same pattern again after wiping.
- Look at dust on the case and the edge of the protector too.
- A screen left on for long tires the eyes, so check only as much as needed.
FAQ
Why show several colored screens?
How well fingerprints and oil show up depends on the background; they appear as dark marks on a bright white screen and as reflections on a dark one. Going through white, black, gray, colors and the grid while tilting the screen helps you find marks on the surface without missing any.
How do I tell a scratch from a smudge?
If it disappears when wiped it is a smudge such as a fingerprint or oil; if it stays and looks like a line at certain angles it is probably a scratch. This tool alone cannot tell a problem inside the display from one on the surface, so treat it as a reference.
How should I clean the screen?
With the device off, wipe first with a dry microfiber cloth, and if marks remain, dampen the cloth slightly with water or a cleaner the manufacturer recommends. Do not spray liquid directly on the screen or use rough tissue. Follow the device maker's guidance for exact methods.
Notes & limitations
This tool is a display aid for visually checking marks on a screen surface and does not diagnose faults or defects. If you suspect a defective screen or a warranty issue, contact the manufacturer's service center.