Does my razr max know it's in my holster and how does it know?

[lmpmd]

My razr max is in a case and goes in a holster and then goes on my pants belt. I was told that there's a "in pocket" or "in holster" detection. But there's no magnet. So how does the phone know it's in my pocket or in it's holster? And if stuff is running and using lots of batteries (say I left it recording a video running) do those functions stop/go away and the unit go into some kind of power saving mode once in my pocket or in it's holster? My prior blackberry did this kind of stuff when in holster (due to the holsters magnet) and I'm wondering if the razr does too?

 

[BaSHa]

I'm pretty sure the "in pocket detection" went away when ICS came out.