The Nokia X may have been running a forked version of Android from the get go, but anyone who has been around Android long enough knows that someone would be most likely working tirelessly to get the device onto something a little more familiar. The downside for many with the Nokia X was that it wasn't running native Android, so that meant no play store, no Google Apps and services, and really, just no Android like they're used to. Thanks to the lovely folks over at XDA though, the Nokia X has been officially hacked and tweaked and is now able to proudly wear a custom ROM that is pure Android with all the fixins'. If you or someone you know has purchased a Nokia X and were waiting for this exact opportunity, this particular forum thread on how to flash a custom ROM to the device is worth a look.
If you were planning on rooting the Nokia X and flashing a custom ROM onto it from the day you decided to buy one, then we'll go ahead and assume that you know already what the process of flashing custom ROMs entails, but just to be thorough, flashing a custom ROM onto a phone like this one for the Nokia X requires root access, and to do that you should have all the details you need from the same page where you can find the steps for the custom ROM. The ROM for the Nokia X was put together by an individual over at XDA who goes by the name of dhacker29, and the ROM was built using some of the source code from Aurora, which is AOSP.(android open source project)The ROM is stable enough to use as a daily driver so if you're worried about all kinds of bugs and most things not working you can lay those fears to rest.
The ROM is based off of Android 4.1.2 Jelly Bean, so it's older software but there should be no complaints considering what software you're coming from. Network connectivity, multi SIM support, the FM radio, the camera, Bluetooth and GPS all seem to be working just fine says the developer, and that there are no known issues at this time. That doesn't mean that something can't pop up. Other inclusions here are obviously the Play Store, Google apps, and really the best parts of having stock android. If you're wanting to give this a try head over to the XDA thread to get started.