How to tell an original display from an aftermarket one

A replaced screen is not automatically a problem. An undisclosed replaced screen is, because it changes the brightness, the touch response, the water resistance and the resale value — and it is the single most common thing left off a used-phone listing. Here is how to tell, in under two minutes, without opening anything.

The three tiers of replacement panel

• Original / service pack. The manufacturer’s own panel, from their service supply. Identical to what the phone left the factory with.
• OEM-grade. Made by the same panel supplier but sold outside the manufacturer’s service channel, or a manufacturer panel bonded to a third-party digitiser. Usually very good. Brightness and colour are close; True Tone and some sensors may not survive the swap.
• Aftermarket / incell. A different panel entirely — often LCD standing in for OLED. Cheaper, dimmer, worse viewing angles, and on an iPhone it disables True Tone and frequently Face ID.

The price difference between the tiers is large, and so is the difference in how the phone feels a year later. This is why every listing on this site states which one it has, with the month it was fitted if it was replaced.

iPhone: the software tells you

Since iOS 15.2, Apple reports non-genuine parts in the phone itself. Go to Settings → General → About and scroll to the bottom. A Parts and Service History section appears only if something has been replaced, and it names the part: Display, Battery, Camera.

• “Genuine Apple Part” — an Apple panel, fitted and paired correctly.
• “Unknown Part” — not an Apple panel, or an Apple panel that was not paired. Either way, it is not the screen the phone was born with.
• No Parts and Service History section at all — nothing has been replaced. This is what you want to see on a phone sold as having an original display.

Two supporting checks. True Tone (Settings → Display & Brightness) disappears entirely when the panel is aftermarket and not properly transferred — if the toggle is missing on a phone that should have it, the screen has been changed. And Face ID: aftermarket panels often break the dot projector’s calibration, so a phone whose Face ID “just stopped working” usually had a screen swap in its past.

Samsung and other Android phones: look, don’t read

Android gives you no equivalent of the Parts and Service History screen, so the checks are physical. Do all five; any one of them alone can mislead.

1. Black test. Open a fully black image in a dark room. A genuine AMOLED goes truly black — the screen visually disappears. An LCD replacement glows faint grey, and you will see the backlight bleed at the edges.
2. Off-angle colour. Tilt the phone to about 45 degrees with a white screen showing. Original Samsung panels shift very slightly blue or green. Cheap replacements shift hard, or wash out to grey.
3. Bezel and adhesive. Look along the edge in raking light. A factory screen sits perfectly flush. A replacement almost always leaves a hairline gap, a slightly proud edge, or visible glue residue in one corner.
4. Fingerprint sensor. On phones with an in-display reader, an aftermarket panel makes it slow, unreliable, or dead. Register a print and try it ten times.
5. Brightness ceiling. Set brightness to maximum outdoors. A replacement panel is usually 30–50% dimmer than the original and becomes unreadable in direct sun.

Samsung’s own diagnostic helps too: dial *#0*# to open the service menu, then run the red, green and blue tests and the Touch test. It will not tell you the panel’s origin, but it will find dead pixels, touch dead zones and colour faults quickly.

What burn-in looks like, and why it matters more than scratches

OLED pixels age unevenly. A phone that spent two years with the same navigation bar on screen will have a faint permanent ghost of it. Test by opening a plain mid-grey image full screen at high brightness — grey reveals burn-in far better than white does. Look for the shadow of a keyboard, a status bar or an app’s header.

A scratch is cosmetic and priced accordingly. Burn-in gets worse every month you own the phone and cannot be repaired without replacing the panel. We do not sell units with visible burn-in at any grade; if you are buying elsewhere, run the grey test before you pay.

Does a replaced screen mean you should walk away?

No — it means the price should be different, and the disclosure should have been made before you asked. A phone with a service-pack panel fitted six months ago can be a better buy than one with an original panel that has a deep scratch across the middle.

What should make you walk away is a seller who says “original” and then, when you open Settings → General → About in front of them, has an explanation ready for why it says Unknown Part. The panel is a fact. The explanation is not.

Water resistance: the quiet casualty

Worth stating plainly because almost nobody does. Any phone that has been opened has lost its IP rating. The adhesive gasket around the display is single-use; even a perfect repair with fresh adhesive is not tested to the original standard. A refurbished phone with a replaced screen or battery should be treated as not water resistant, whatever the model’s specification sheet says. Ours are, and we say so.