A new feature called ScreenTime gives Apple device users data on their phone and app usage, and lets them limit access if they want to cut down. The tool is included in iOS 12, a new version of the iPhone and iPad operating system that will likely be released to the public in September.

Apple CEO Tim Cook told CNN that testing ScreenTime had been a wake-up call for him. “I’ve been using it and I have to tell you: I thought I was fairly disciplined about this. And I was wrong,” he said. “When I began to get the data, I found I was spending a lot more time than I should. And the number of times I picked up the phone were too many.”

However, this revelation about over-use of mobile devices appears to have hit Cook some time later than it occurred to others. The notion of tech addiction has hit the mainstream, in part thanks to former Silicon Valley executives speaking out about it, and some people are particularly worried about the effects on children.

In January this year, two major Apple shareholders—Jana Partners and the California State Teachers’ Retirement System (CalSTRS)—urged the company to introduce tools to help parents limit their kids’ phone usage, as “there is a growing body of evidence that, for at least some of the most frequent young users, this may be having unintentional negative consequences.”

Apple responded to that missive by saying it was “committed to meeting and exceeding our customers’ expectations, especially when it comes to protecting kids.”

Google (GOOGL) is also making a push to combat smartphone addiction. Accused by the likes of George Soros of fostering the problem, Google last month unveiled new tools for Android users that let them monitor usage and schedule breaks from the small screen.