Systems, methods and apparatus for presenting information using idle time slot. In an aspect, when a standby or idle device detects that a user gazes at it, it starts showing contents on a display automatically. In another aspect, when a standby or idle device detects that a user shakes or taps on it, it starts gaze sensing. If the user gazes at the device, it begins to show contents automatically. In addition, facial recognition is used to recognize a user.