Why there is a fungi on my display?

[AC Question]

Hi guys,
I'm using a Samsung Galaxy J7 2015, today when I was using my phone a blue tint started showing on the bottom right side of the display. After some time a brown color spot appeared on the top left corner. Then it started growing. Right now the 30% of my display is looking like an old rusty metal sheet. But the touch is still working. What is happening???

 

[recDNA]

While fungus can grow on some types of glass it is colorless. Perhaps there is something below the screen? How about some pictures?

 

[smvim]

Your J7's display is a combination of a digitizer, the capacitive touch surface that your finger interacts with, and the actual screen itself, an AMOLED, what your eyeballs interact with.
Since the touch part appears to be OK, it sounds like the AMOLED is starting to fail. At this point you should give some thought to either upgrading to a new phone or having this one repaired. But in the meantime, before the screen fails completely, be sure to backup all your personal data NOW.