Two big investors want Apple to do more to curb what they call iPhone addiction among kids.
An open letter from the California State Teachers' Retirement System and New York-based Jana Partners LLC expresses growing concerns about how devices and social media are affecting children.
The letter cites studies and surveys on how heavy use of smartphones and social media negatively affect children's mental and physical health.
One remedy the investors would like to see is enhanced mobile device software so parents have more options for protecting their kids' health.