How does ' wake up on double tap' works?

[Praj]

I have set ' wake up on double tap' on my Lumia 730.
I want to know how does it work?
Does it drain the Battery?
Concept behind it...
TQ u guys.

 

[xandros9]

The touchscreen will always remain on and ready to receive input and interpret double taps.

If the proximity sensor indicates the face of the device is covered, like when the phone is in a pocket, double-tap will be disabled to save power.

It uses power, no doubt about it, the question is, HOW MUCH power does it use?
I have it enabled all the time on my 920, hasn't resulted in terrible battery life, so I think the convenience is worth what relatively little power it uses.

 

[wincenfan]

It's tricky to get it working all the time on the 730. Like, when removing it out of the pocket, it does not work most of the time. When placed on a horizontal surface, there is no problem getting it to work. So, I'm still unsure as to how to get it to work 99% of the time.

 

[xandros9]

It's tricky to get it working all the time on the 730. Like, when removing it out of the pocket, it does not work most of the time. When placed on a horizontal surface, there is no problem getting it to work. So, I'm still unsure as to how to get it to work 99% of the time.

I've heard people have had luck with a slower double tap, at least on the 830.