www.chinaphonearena.com

Since i have installed android kitkat whatsapp notifications doesn't arrive until i unlock my mobile phone. if i don't unlock it they don't arrive
Should i install a older version of whatsapp?
What may i do?

I'd recommend contacting the WhatsApp developers. Ask them if it's a known issue and see if they have a fix.

Try poking around here and see if anything comes up:
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