You want to take a selfie but your arms are too short? A group photo is made but also the photographer shall be in the picture? These are two of many applications of a remotely operated camera.
Install this app on two devices: One will act as camera the other is connected via Bluetooth and can remotely control it. On the remote control device the user interface is like on a camera application: the preview is displayed, the flash mode can be chosen and by pressing the shutter button a picture is taken. Afterwards the picture is available in the gallery of both devices.