Playing WhatsApp audio messages after locking the screen I just switched from an android phone to an iPhone. In android I was able to (continue to) play WhatsApp audio messages after locking the screen or even when switching between apps. 

This doesn't seem to be possible in iOS, am I wrong?
Even I've been searching this for a long time. It seems not possible (atleast as of now). 

You can use whatsapp web via safari. It continues playback even if the screen is locked or if you've switched app. You can control playback via the control centre. 

Cheers!