I am very happy to say that Samsung Galaxy J7 is the best model of Samsung in means of battery.
It has battery power of 3300mAh but it is better than 4000mAh battery of some other phones.
This mobile comes with 3gb ram which is enough for gaming and official use.
The problem faced by me with this phone was that after buying this phone within a month the software of this mobile was crashed but it was in warranty period that's why I get it repaired within two days.
Otherwise till now I didn't faced any problem yet.
I recommend you also to buy this phone as a budget phone.
Thank you