Facebook and other social media firms should alert children if their parent or carer is monitoring their online activity, under proposed guidelines to improve child internet safety in the UK.
Turning off the ???like??? function, and limiting data collection and geolocation tools on popular platforms, such as Instagram and Facebook, are among a 16-point list of recommendations for age-appropriate design released by the Information Commissioner???s Office.
It said ???nudge??? techniques, which platforms employ to encourage users to engage in a certain way, including ???streaks??? on Snapchat and Facebook ???likes???, should not be used to try to keep under-18s online for longer.
Other recommendations under the ICO???s proposed code of practice for internet firms, which the platforms would be responsible for enforcing, include:
Limiting how children???s personal data is collected, used and shared by social media companies.
Making ???high privacy??? the default setting for children using social media platforms, including disabling geolocation tools and targeted advertising as standard, unless there is a compelling reason not to.
Requiring social media companies to show that all staff involved in the design and development of services likely to be used by children comply with the code of practice.
Introducing robust age verification checks on platforms or treat all users as if they are children.
Companies that do not stick to the code could face fines of up to 4% of their global turnover, around $1.6bn for Facebook. The consultation will last until the end of May, and the final version of the code of practice, touted as a new international standard, is expected to come into effect by 2020.
Elizabeth Denham, the information commissioner, said: ???This is the connected generation. The internet and all its wonders are hardwired into their everyday lives.
???We shouldn???t have to prevent our children from being able to use it, but we must demand that they are protected when they do. This code does that.???
The ICO sought views from parents and children while developing the code of practice, as well as those of designers, app developers and academics.
The NSPCC children???s charity said social networks had ???continually failed to prioritise child safety in their design???, resulting in ???tragic consequences???.
???That???s why it is vital this code requires children to be given the highest privacy settings by default and forces firms to act in the best interest of children,??? the NSPCC???s associate head of child safety online Andy Burrows said.
???This design code from the ICO is a really significant package of measures, but it must go hand in hand with the government following through on its commitment to enshrine in law a new duty of care on social networks and an independent regulator with powers to investigate and fine.???
Lady Beeban Kidron, the chair of the 5Rights Foundation and who led the parliamentary debate about the creation of the recommendations, said the code represented ???the beginning of a new deal between children and the tech sector???.
???For too long we have failed to recognise children???s rights and needs online, with tragic outcomes,??? she said.
???I firmly believe in the power of technology to transform lives, be a force for good and rise to the challenge of promoting the rights and safety of our children. But in order to fulfil that role, it must consider the best interests of children, not simply its own commercial interests.???