Abstract: The invention provides a computer implemented method of displaying content on a screen of an electronic processing device. The method comprises a first step of receiving content to be displayed on said screen at a data processing application on said electronic processing device. The data processing application is a dedicated application for processing said received content data and is configured to perform various steps including processing the received content data into a format suitable for display on said screen. The data processing application is also configured to monitor at least one sensor of the electronic processing device such as the device's camera to receive at least one biometric data input during display of the content on the screen and to cause either a halting of the display of the content or a blurring of the screen in response to a determination of a predetermined change in said biometric data.