Nokia X is the first ever Android running smartphone from well known manufacturer Nokia. It is a budget phone launched in a month ago at affordable price of Rs. 8,500/- So, far there was just a single small updated rolled out for the device that didnt brought any major change to the phone.
First of all, it is not the pure Android smartphone, Nokia has done several coding in the OS and created its own operating system with all Microsoft services instead of Google. However, we can revers that by rooting the phone. Now, if you want to get pure Android Jellybean 4.1.2 operating system on your Nokia X, it is possible. You just need to install this small Custom ROM and done.
It is Aurora Vanilla Android 4.1.2 running Firmware build upon Linux 3.4.x kernal. In order to flash this ROM, your device must be running on Nokia X software platform 1.1. For the detailed step by step process, you should check out this guide.