Adults and teens turn to 'dumbphones' to cut screen time
According to a study by Harvard University, using social networking sites lights up the same part of the brain that is also triggered when taking an addictive substance. This has raised concerns about phone habits among youth.
In the UK, research by Ofcom estimates that around a quarter of children aged five to seven years old now have their own smartphone.
Links have been shown in some studies between use of social media and a negative effect on mental health - especially in children.
