According to an example aspect of the present invention, there is provided an apparatus comprising at least one receiver configured to receive an identifier and an indication of at least one new touch point detected on a touch sensitive screen, and at least one processing core configured to cause transmission of a disable touch point instruction, to determine whether the at least one new touch point disappears from the touch sensitive screen, and responsive to a determination that the at least one new touch point disappears from the touch sensitive screen, to associate a location on the touch sensitive screen with the identifier.