For those again facing issues with WhatsApp on Nokia X family of devices, here is the help!!
1) Uninstall and completely remove any previous WhatsApp version from your devices
2) Download the APK file by clicking here on your devices or on PC. If you have downloaded the APK file on your PC, you need to transfer it back to your device by connecting it to PC.
3) Just make sure that, you have done this already, open Settings, scroll down and tap on security —>Here, tick the box in front of Unknown Sources–>Accept the warning.
4) Install the file by tapping on it and following instructions
This should give you WhatsApp back on your devices. Do let us know whether it worked.
You can watch our Nokia X and Nokia XL hands-on videos including unboxing, UI demo, full settings walk-through, native apps and review etc by clicking here and here. Catch the full Nokia X and Nokia XL coverage including extensive hands-on, camera comparison, display test, gaming and full review by clicking here and here.