Why your selfie lies about your color.
Because a selfie is your camera's guess, not a measurement. The front camera softens detail, HDR and Photographic Styles re-tone your skin before you see the shot, and the bulb or window casts its own color the phone tries to “fix.” You're looking at an interpretation.
The phone is tuned to flatter, not to measure
A phone camera is built to make photos look good, not to measure them. The front (selfie) camera softens detail, and features like Photographic Styles and HDR re-tone skin on the way to the picture — so the color you see has already been edited by the time it reaches your screen.
It also guesses the light. Your phone doesn't know whether a warm cast is a tungsten bulb or your actual undertone, so it makes a call and bakes that call into the JPEG. That's why the same face can look like a different person in every app you upload it to.
What the room adds on top
Screens and bulbs cast real color onto your skin. A monitor throws amber or blue, a warm bulb adds enough tint to shift a warm-cool reading, and a colored shirt bounces its hue up onto your jaw. None of that is you — but a tool reading straight from the photo can't tell the difference.
How to give it a real measurement
Two things turn a photo into a measurement. Shoot in even, indirect daylight — a north-facing window is best — so one clean light is on your face. And for a calibrated read, put a gray card in the frame: the neutral reference that lets the math undo whatever the light and the camera did and correct the whole photo back to standard daylight.
The free read deliberately skips the gray card, so you can watch your season slide with the light — proof of how much your camera was guessing.