Why used phones need a dedicated test
Used devices may have long-term static content wear, accidental pressure damage, or hidden dead pixels that sellers do not notice.
Testing on plain fullscreen backgrounds strips away app clutter and makes those issues much easier to verify.
The fastest buying checklist
Check black for burn-in, gray for banding, white for tint, and red, green, and blue for pixel defects. This sequence covers most common display risks quickly.
Also inspect the screen at medium and high brightness so you can compare whether the issue changes with output level.
How to decide if a flaw matters
Small single-pixel flaws may be acceptable depending on price, but strong burn-in, uneven tint, or obvious banding can affect daily use and resale value.
If you are unsure, compare the defect against normal content to judge whether it will be distracting in real life.
FAQ
What should I test first on a used phone?
Start with black, gray, and white, then move to primary colors for dead pixel and subpixel checks.
Can a seller hide burn-in on the home screen?
Yes. Burn-in is often much easier to see on plain fullscreen patterns than on colorful app screens.
Should I reject a phone for one dead pixel?
That depends on price, location, and your tolerance, but strong burn-in or multiple defects are more serious warning signs.
Run the test now
Use the OLED Test homepage to open fullscreen colors, inspect uniformity, and compare panel behavior in real time. The browser-based workflow is fast, free, and works well for quick repeat checks.