Apple says it has new features and enhancements in the pipeline to help parents control children’s use of iPhones and other devices. The company was responding to a pair of Apple shareholders who wrote an open letter last week arguing that the iPhone-maker needs to tackle what’s seen as a “growing public health crisis” of smartphone addiction in young people.

In a statement released to The Wall Street Journal and other outlets, Apple said: “We have new features and enhancements planned for the future, to add functionality and make these tools even more robust.” The company also stressed that it takes the issue of mobile addiction among young people very seriously:

“We think deeply about how our products are used and the impact they have on users and the people around them. We take this responsibility very seriously and we are committed to meeting and exceeding our customers’ expectations, especially when it comes to protecting kids.”

The company pointed to existing parental controls built into iOS that help parents moderate content including apps, websites, movies, songs, and books. The tools can also restrict cellular data, password settings, and other features. Apple notes that anything children can download or access online can be blocked or restricted and that some of the parental controls have been offered since 2008.