Im searching for an android 4.4 custom rom for a nokia 520, because android 6.0.1 is very unstable and android 7.1 very laggy, thinking this nokia has got 512 mb of ram, i think that android 4 is the best option fot this phone.
The rom that actually am using is from android 4 Lumia, right now i am testing the kit kat romAndroid 7.1 works a little bit better than Android 6. There is an Android 4.4 ROM by @thinhx2 but it's more outdated and unstable than latest Android4Lumia LineageOS 13.0/LineageOS 14.1 ROMs.
There aren't any ROMs with working SIM.I'm looking for a rom with working sim. Can anyone help?