Hidden eye is a app used to know who tried to snoop your android device,it automatically take a photo via front camera and save it to gallery in DCIM folder you can also configure to save image in your dropbox account. After installing tap ON button and activate device administrator for it thats all you need to do rest Hidden eye will take care.Every time when some try to unlock your phone if the password fails this app automatically take a photo via front camera silently,It also makes sound alarm after three attempts.