OLED phones like Samsung S3, S4, or S5 are more susceptible to screen burn-ins or ghosting than LCD phones, but LCD screens are still also capable of getting burn-in.  I don’t know if IPS display phones are vulnerable to burn-ins caused by when people leave static images for long hours.  Regardless there is still a fix you can do to fix it.  I had burn-in on my Galaxy S4 and it was clearly visible.  What I did was use an app from the Google Playstore called “Screen Test and Fix”.  

Screen Test and Fix

Screen burn in test and fix https://play.google.com/store/apps/details?id=com.rane.screentestfix The big difference that this app has over other similar apps which also fix burn-in, is that this one actually gets rid of the burn-in by very rapidly flashing the different colors to get the stuck pixels excited and change colors.  It really works.