Abstract: A computer-implemented method of triggering an action based on behaviour of a user consuming content at a user device, the method comprising receiving content change signals at a processor executing a content change detection algorithm, wherein the content change signals denote a change of content on the user device; wherein the detection algorithm compares the content change signals with a content change behaviour associated with that device to detect a surfing condition and generates a triggering control signal for triggering an action when the surfing condition for that device is detected.

Abstract: A computer-implemented method of triggering an action based on behaviour of a user consuming content at a user device, the method comprising receiving content change signals at a processor executing a content change detection algorithm, wherein the content change signals denote a change of content on the user device; wherein the detection algorithm compares the content change signals with a content change behaviour associated with that device to detect a surfing condition and generates a triggering control signal for triggering an action when the surfing condition for that device is detected.

Abstract: A computer implemented method of controlling access to content to be viewed on a viewing device, the method comprising: selecting desired content to be viewed on the viewing device; displaying auxiliary content which is required to be viewed while preventing display of the desired content on the viewing device; after displaying the auxiliary content, displaying at least one user engagement element defining an expected user activity; detecting if a user has engaged with the user engagement element in accordance with the expected user activity and if so, displaying the desired content on the viewing device.