Since a scathing open letter to Facebook chief executive Mark Zuckerberg about a new social media app for children was published on January 30, Australian parents, teachers and researchers have spoken up about whether they support the backlash.

The letter, written by a group led by the Boston-based Campaign for a Commercial-Free Childhood, urged Mr Zuckerberg to halt the distribution of Messenger Kids, a new app rolled out in the US in December 2017.

The free app is aimed at children between six and 11 and allows them to message friends, video chat, and send photos with parental permission and supervision.

The system does not allow people to search for children, nor does it feature targeted advertising.

The open letter, signed by more than 100 child health experts, implored Facebook to “do better” by “leaving younger children alone”.

It also cited studies linking excessive social media use to addiction, mental health issues, unhealthy sleep and poor socialisation.

“A growing body of research demonstrates that excessive use of digital devices and social media is harmful to children and teens, making it very likely this new app will undermine children’s healthy development,” the letter said.

“It is disingenuous to use Facebook’s failure to keep underage users off their platforms as a rationale for targeting younger children with a new product.”

Although Messenger Kids is yet to spread globally, University of Queensland social media researcher Dr Nicholas Carah said he didn't see anything that would stop the app from rolling out quickly in Australia.

“Australia has always been an early adopter market for new technology,” he said.

“You get a quick network effect because, if you think about something like a smartphone or a social media platform, they rely on other people in your social network also using them.”

He said the app would likely raise controversial issues about the limits of parental control.

“The issue here is that for parents and kids, it feels like very little of this is on their terms and that so much of this is set by the terms of the platform and driven by [their] commercial agendas,” he said.

“What you’re seeing now is advocacy groups that represent children and parents saying actually, we deserve much more of a say in how these platforms interact with our kids.”

Research and development manager for social media safety group Eyes Open, Dann Munn, said Messenger Kids would be a useful tool to prepare children for the “responsibilities of the internet”.

“Whether we like it or not, kids are operating in an online world and we can’t shut them down to that,” he said.

“We have to expose them earlier, but do it safely.”

Mr Munn also said he disagreed with comments from the open letter, which claimed children were “simply not ready” to have social media accounts.

“They’re not ready to operate on sites which are outside of the age-appropriate levels, but they are absoutely ready to use age-appropriate sites that are well set up and well managed,” he said.

He said the app would be useful as long as it did not mine data from child users.

“It’s absolutely critical that they don’t do that for kids.”

Scott Downman, Brisbane dad to 12-year-old Sariah, has strictly limited her exposure to social media and is wary of new technology aimed at younger children.

“We’ve put filters in place as best we can to monitor it. We’re aware that it’s not perfect, but we’re also aware that you can’t live in isolation from this stuff either,” he said.

“If you just cut kids loose at 12, I think it’s dangerous. They don’t have the maturity, they don’t have the understanding of how the world works for us to do that.”

Mr Downman said he was uncomfortable with the idea of Facebook targeting younger demographics, but ultimately it was up to parents to assume responsibility.

“Rather than an open letter, people just need to be informed about what it does and how it works and then they can make their own decision.”