App which works when phone is switched off

Hi All,

I am interested in understanding what it takes to build a app, which works when is switched off as well?

I searched internet but couldnt find valuable information. You can post the link here so that I will go through them.

I see that there are couple of applications which works when phone is off, like clock. That works even when phone is off or that syncs with the current time when we switch it on. I know there is a battery in PC which works even when we turn it off.

So can we design some app which works always? to find the location of the person?

Recently , an incident happened in hyd, a girl was kidnapped and she informed someone about that using her phone, later her phone is switched off.

IF phone is off, then there is no way we can find out rite?

So, is there a way we can design a app which runs continuously 24 hours which can say the location of any user?

Probably that can be password protected, I enter mobile number and I get the location of the user?

I think I am sounding stupid, but I am sure this is not impossible.