Therere several things you need to know before buying Galaxy J1.
1 - If you are Android lover, you need to know that It doesnt consist of latest version of Android, but It comes with Android 5.1. If you want to have an android mobile of newest level, this may be an issue.
2 - The most irritating thing you will find about this phone is its RAM of 1 GB. Believe me, thats gonna suck. It may result in freezing or slowing down the processes. Heavy games can also not be enjoyed smoothly with this.
3 - The pixel density is not good. And If you need to play HD videos, you may not get expected video quality.
4 - Everything else is okay. It has 1.3 Ghz Processor which is not very much, but okay.
5 - It has a battery of 2050 maH which is not enough.
6 - Camera quality is good as It has 5 MP autofocus camera. It also has a secondary camera of 2 MP.
7 - It has 8 GB of storage and its microSD can be extended upto 256 GB.