Is there anyway to configure Cortana in a way it understands our voice even when the phone screen is off, as we say "ok google" in Android? Cortana seems to get activated manually only. Why has Microsoft not thought of this option, which is very handy? Is it not possible in Windows Phone architecture? Note: My phone is Lumia 435 Dual SIM
Starting with Windows Phonee 8.1.1, Microsoft introduced "Hey Cortana", which translates to a passive listening capability as you'd like it. It is restricted to few phones at the moment with special, dedicated hardware, as I suppose it would be a significant battery drain otherwise.