Those who work extra hours via smartphones are more prone to insomnia and other complaints, reports the Daily Mail.

They wrote: ‘Information and communication technologies, such as computers and smartphones… have the potential benefit and the potential inherent danger of making it possible for employees to be available any time and anywhere.

‘This changes not only our work organisation, but probably also our patterns of social participation and integration.’

They added: ‘Free time should be free time, otherwise it must be expected that it cannot fulfil functions of recovery and recuperation.’