Samsung Galaxy J7 Prime is an extremely good phone. It has 5.5 inch Full HD TFT display which has excellent pixel quality and the screen quality is very nice to protect the screen it has also corning gorilla glass. It has updated OS which is Marshmallow.
I would say that ram management is very good it has 3gb ram which is excellent with memory 32gb and it is expendable memory.
It has 13mp rear camera which has autofocus which is an excellent it also has rear 8mp camera which is good not bad.
Yes it has 4G, NFC, OTG support.
The sound quality is a bit low but it was ok not too low.
Worthy for your money.