Camera and flash test
Opens the cameras the browser can reach and switches the flash on. Look for a black picture, spots, haze, a pink or green tint, and focus that never gets sharp.
Open this page on the phone you want to test. Press Back or the close button to stop at any time.
How to do it
- Tap Start and allow the camera.
- Switch between the cameras at the bottom. Point each one at small text.
- Tap Flash if it shows, and check the front camera too.
What the result means
- Sharp and clean on every camera: the cameras the browser opened work.
- Spots or haze in the same place: dust or damage inside the lens, or a scratched cover glass.
- Black picture: a dead camera or a camera another app is using.
What a browser cannot see: whether the phone is really the model it claims (copies run on a different processor), how worn the battery is, whether the storage is as big as it says, and whether the system was modified. The free Knowfone app for Android checks all of that and every part above in about 7 minutes, then answers: good to buy, buy only at a lower price, or don't buy.
Questions
Why can I not see all of my phone's lenses?
Many phones only give browsers the main back and front cameras. Open the phone's camera app to try the ultra-wide and zoom lenses.
Are pictures saved or uploaded?
No. The picture is shown live and nothing is recorded or sent.
More phone tests
Buying a used phone? Read the 14-step checklist or look up the real specs of popular models.