‘Shout, clap, honk like a goose – from the creative to the amusing, Triggertrap Selfie opens up a whole new world of snapping self-portraits,’ Triggertrap said in a statement.

Explaining how it works, the firm added: ‘Open the free app, hold the iOS device at arm’s length with your face in shot and shout, good and loud.

‘As soon as the shout hits the required number of decibels, the pixelated screen will clear and the camera snaps a selfie.

‘Your screaming work of art is saved to your camera roll, and you can share it straight to Twitter from inside the Triggertrap Selfie app.’

The app uses Triggertrap’s smart face detection to ensure a photo is taken only when a face is in the frame.

Triggertrap Selfie is available on the iOS app store and is free to download.