I can't think of a single camera phone where the button doesn't start the camera.

Then I pressed the second button and the port engine started.

Once they got into the corridor, Inara hit the button and the room started to close up again.

He pushed a button and the video started rolling.

He presses a button on the control desk to start it.

He hit the button and the lift started once again.

Kirk sat down at the radio and pressed the button that by now he had learned started the recording.

One of the girls in the bunker hit a button and a loud siren started to sound.

These buttons start the automatic process of driving the train.

The on button simply started a flight from Mars.