The Sticker Sensor is a type of sensor introduced in LittleBigPlanet. The Sticker Sensor senses if the player stamps the appropriate sticker onto the object the sensor is attached to.
The first design, which is in LittleBigPlanet and LittleBigPlanet PSP, is decagonal with a bolt on each half. It has a metallic look, and in the middle is a squiggly yellow line. The sensor will also flash completely white, then return, signaling that it hasn't been activated yet. If you try to put the wrong sticker, it will make a "du doyng... du doyng..." sound, and will flash red. Putting the appropriate sticker will make it flash green and faster, and will then stay in a bright green flash, signaling it has been activated.
The LittleBigPlanet 2 design is more electronic, it has the Popit Stickers and Decorations icon on a black circular screen. The screen is attached to metal in the shape of a football. The icon flashes yellow, and flashes red when the sticker is wrong. It flashes faster and green when the right one is used, and become permanently green when the sticker is stamped.