Hi dear customers, I hope this secret can help you test your phone.

If you but a new Samsung phone, or your Samsung phone have some problem of screen, you can put *#0*# on your phone keyboard.

*#0*#

And then you can test by yourself, you will know each sensor or each color whether works fine.

Lcd testing

 If you are a repair man, I think the test touch funtion is important, you can click the touch on picture above, you will see the picture below

Touch test

 traces the path with your finger

Finger test

Good job, pass!