stelthie
When a person uses the camera on a cellular phone to mislead others (esp. a large crowd of strangers) to pose for a picture, while taken a selfie of themselves. This is done by switching to the front facing camera on a mobile phone, without the subjects being aware. From a 'stealth' 'selfie'.
A stelthie was taken when an unwitting bridesmaid asked a stranger if he would take their picture, and they instead ended up with a picture of him.