Color differences and readability of the same pdf - Neoreader vs acrobat

Hi, 

I'm a new TAB X user and I don't know if I'm missing something, but the same pdf opened with Acrobat installed on the device versus NeoReader looks different. I'm not even talking about speed, definitely in favor of NeoReder but colors and readability. It's as if neoreder sharpens the quality of pdfs making them definitely better to read. 
I would love to use this program if it were not for the fact that I am not able to save notes taken in it directly to the onedrive cloud. 
Question: can I somehow adjust the colors and readability of pdfs in external applications? And if so, what are the optimal values for reading pdfs. 
Sincerely
Adam

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