Have you ever seen your finger touch data on the mobile screen like below? Any where you touch on the mobile phone screen will be displayed, it tracks your finger touch. On the top of your screen, you can find the accurate position info of your current touch.
If you see a screen like above, you should have enabled the “Show pointer location” option on your Samsung mobile phone. You can go to enable or disable it from Settings >> Developer options >> User interface >> Show pointer location. Once you turned on this option, you will see screen overlay shows your current touch data on any screen you are.
Note since Android 4.2.X, the Developer options is hidden by default. If need, you have to manually turn it on. Sometimes we have to enable it. For example, you need it if you want to recover deleted text messages from Samsung galaxy phones. If you want to use a mobile phone transfer or management software on computer, you may also need to enable this option. Check out this guide see how you can enable Developer options and USB debugging on Samsung phones.