Two large investors in Apple Inc. were right to sound the alarm last week about addiction to smartphones and the impact on the mental health of teens. But can Apple be trusted to perform unbiased studies or develop meaningful solutions on its own?

Apple is in the business of selling more iPhones, just as app makers, mobile phone service providers and social media companies are keen on keeping users locked on their devices for hours on end. Just as tobacco companies are incapable of regulating themselves, it is difficult to imagine Apple implementing changes that would decrease usage in its devices.

What is really needed is more independent study, public awareness and likely some regulation. In their letter to Apple, Jana Partners, an activist hedge fund, and the California State Teachers' Retirement System, one of the largest public pension funds in the country, said the average American teen who uses a smartphone receives their first phone at age 10 and spends 4.5 hours a day on it — excluding texting and talking.

Nearly 80 percent of teens check their phones once an hour and 50 percent report feeling addicted to their phones. "It would defy common sense to argue that this level of usage, by children whose brains are still developing, is not having at least some impact," the investors wrote.

The letter cited other alarming research:

  • Teens who spend five hours or more a day on electronic devices are 71 percent more likely to have a risk factor for suicide than those who spend less than one hour, according to research by Jean Twenge, a psychologist at San Diego State University.
  • Teens who spent five days away from smartphones and other electronic devices had improved comprehension of nonverbal emotional cues, a study by UCLA researchers found.
  • Teens who used social media devices regularly before bedtime get less sleep, which can lead to physical and behavioral problems, another study found.

It is not just teens who are impacted. A survey by the American Psychological Association found adults constantly checking electronic devices led to increased stress.

Jana Partners and CalSTRS, which own about $2 billion in Apple shares, called on Apple to convene an expert committee to conduct research and develop new tools, such as easier-to-use parental controls that could limit screen time.

The investors believe that taking proactive steps can blunt the growing re-evaluation of the effects of technology on society. Facebook, Snap Chat, Google, Amazon and other tech giants are also facing questions about their reach and impact into everyday life.

The investors believe that being a good corporate citizen can also be good business in the long run. But experience shows that profit-driven companies are usually focused on what may be best for the bottom line, not for society as a whole.

Big tobacco and pharmaceutical firms, for example, have been known to suppress damaging studies and fund positive research. A more effective approach would be independent government research that examines the impact of smartphones and other devices.

For years, smoking was considered acceptable and even encouraged.  We know better now. It's time to get smarter about phones.