Mumsnet has been lambasted for 'normalising' smartphone ownership among primary schoolchildren after using a six-year-old in a marketing campaign.
The parenting forum has launched a £279 phone designed to 'put child safety first and give parents peace of mind'.
A promotional piece documents how two boys tested the device - enjoying apps such as YouTube - aged just nine and six years old.
It sparked fury among Mumsnet users who accused the parenting forum of being 'out of touch' and chasing revenue over good advice and common sense.
The row comes as the Government considers Australia-style measures to limit or ban social media for under-16s, while new advice warns against more than an hour of screen time for under-fives.
Campaigner and actress Sophie Winkleman said: 'I would love society to move away from the idea that children need constant digital stimulation in their lives.
'IPads and computers offer endless entertainment while damaging a child's imagination and their ability to create their own fun.'
'The 'advertisement feature' for the Other Phone documents how the device became part of 'day-to-day life' for the sons of Mumsnet's chief technology officer, Matt.
The parenting forum has introduced a £279 smartphone specifically built to prioritize child safety and offer parents reassurance (pictured: stock photo of child using a smartphone)
Harrison, nine, and James, six, are described as 'first-time phone owners' and are shown in a series of pictures staring at their screens.
In one image, they appear to be at the end of a meal, with dishes in front of them.
The piece states: 'Harrison had been asking for a phone for a while, especially since moving to middle school where more of his friends have devices. James wouldn't normally have had one yet, but, as Matt explains, 'sibling dynamics made a staggered approach unrealistic'.'
The promotion advises readers that Harrison felt the phone was 'cool' while 'screen time overall dropped' compared to the use of a shared iPad at home.
It states that the family noticed 'no negative behavioural changes', adding: 'Instead, Matt reports increased independence, a greater sense of responsibility and signs that trust was being taken seriously.'
Iona Wallace, co-founder of the Learning Consultancy, which helps families support children's development and wellbeing, said: 'Many parents feel increasing pressure to give children their own phone earlier than they'd like, particularly as it becomes more common among peers.
'However, we should be cautious about normalising smartphone ownership at a young age. There is no developmental benefit to children owning or having independent access to a smartphone, and growing evidence suggests this early exposure comes with risks.
'While phones can serve a purpose for communication or safety, delaying ownership supports healthier long-term habits. As one of the original and most influential parenting platforms, Mumsnet has an important role to play in helping parents navigate these decisions. In light of the growing evidence, that role carries a responsibility to challenge the normalisation of smartphone ownership among children, rather than unintentionally reinforcing the idea that it is necessary at an increasingly young age.'
Health Professionals for Safer Screens, a medical campaign group, cautioned: 'From a health perspective, professionals would not generally recommend the use of phones as a form of entertainment or as a routine necessity for children as young as six.
'There are well-established concerns around the broader impacts of early and excessive screen use, including effects on sleep, attention, and global development.
'While these safer devices may have a place in certain circumstances, they should be used thoughtfully and sparingly, with a clear focus on communication needs rather than general use.'
Mumsnet users also queried the promotion, with one branding the site 'out of touch' and adding: 'Why is mumsnet actively pushing phone usage for primary aged children? [...] I am quite honestly shocked and yes, I am clutching pearls. Do better Mumsnet.'
Another said: 'I thought the same, absolutely bizarre. Six-year-olds should not have phones, obviously'. A further comment reads: 'I thought this too. Just shows revenue is more important than good advice and common sense!'
Mumsnet's CEO Justine Roberts said: 'It's bonkers to suggest Mumsnet is encouraging or normalising smartphone use among young children. Through our Rage Against the Screen work we have been encouraging parents to delay smartphone adoption for as long as possible, and [we are] clear that the government must act with stronger regulation, including restrictions on social media for under-16s.
'But we cannot ignore reality. Ofcom data shows a significant minority of primary-aged children already have smartphones. For families in that position, ignoring them does not make them safer.
'That is why we built the Other Phone; whilst we wait for a government to act and change that default, we wanted to do something about it. The Other phone was designed to put children's wellbeing first and give parents control—something that Big Tech has singularly failed to do.'