How to Detect Hidden Camera in Changing Room?

HOW TO DETECT ?
Make sure that your mobile phone can make a call.
Then enter into the changing room and try to make a call
If you can't make a call , There is a hidden camera !
this is due to the interference of fiber optic  cable during the signal transfer .

HOW TO DETECT A 2-WAY MIRROR ?
when we visit toilets, bathrooms, hotel rooms, changing room or etc. how many of you know for sure the seemingly ordinary mirror hanging on the wall is a real mirror or actually a 2-way mirror? there have been many cases of people installing 2-way mirrors in female changing rooms or bathroom or bedrooms. it is very difficult to positively identify the surface by just looking at it. so, how we do determine with any amount of certainty what type of mirror we are looking at ?

CONDUCT THIS SIMPLE TEST:
1)place the tip of your fingernail against the reflective surface and if there is a gap between your fingernail and the image of the nail, then it is a genuine mirror.
2) if your fingernail directly touches the image of your nail, then beware, it is a 2-way mirror !
3)the reason there is a gap on areal mirror, is because the silver is on the back of the mirror under the glass.
4) whereas wit 2-way mirror, the silver is on the surface. Keep it mind !
5)make sure and check every time you enter in hotel rooms.