It's hard to avoid giving your child a smartphone in this new digital age, but some parents around the world are looking to buck the trend and seek out guidance on how to protect their kids from the harms of smartphone use.

Smartphone Free Childhood, a recently founded U.K. organization is aimed at uniting parents who are not giving their kids smartphones. It has since expanded internationally as research around the topic grows.

Young people who acquired a phone before the age of 10 reported worse mental health outcomes than those who acquired a phone over the age of 15, a Sapien Labs study of 27,969 18–24-year-olds from 41 countries last year found.

Meanwhile, at least 42% of children in the U.S. had a smartphone by the age of 10, according to a Common Sense report in 2021.

Some parents give their children smartphones for safety reasons, including being able to contact them and track their location when they're outside the home, but this may lead to mental health harms.

"The analogy that I often have in mind with the cell phone and technologies today is the automobile and when the automobile was first invented people were thrown from their cars and the number of fatalities was dramatic," Kathleen Pike, CEO of One Mind at Work and psychology professor at Columbia University Irving Medical Center, told CNBC Make It in an interview.

"There were no seatbelts, there were no airbags. The construction of the chassis made people vulnerable and in recognizing the vulnerabilities that came along with this tremendous technological innovation, we instituted regulations and better design and policies that protected the health and wellbeing of drivers and passengers. We're in the earliest days with cell phones and technology broadly where we need to do the same," she said.

Columbia's Pike and Zach Rausch, a research scientist at New York University Stern School of Business and lead researcher for Jonathon Haidt's number one New York Times bestseller "The Anxious Generation," shared five tips on how to avoid giving your kids a smartphone.

Organize with other parents

Being the only parent refusing to give your child a smartphone can be isolating for both you and your kid, Rausch said.

"Before you act on your own, find a couple of your kid's friends, three to five of them. Talk with their parents, and if you all together decide to delay smartphones till high school, then it's going to be much easier because then you can say 'Well, Johnny is also not getting his smartphone till 14," he said, adding that this will make the conversation "much more digestible" for the child.

Pike also advised working with other parents. She shared an anecdote about a parent whose child's fifth grade class formed a parent-teacher association.

"The class parents, as a collective, agreed that they would postpone giving their kids cell phones until they entered middle school. So when nobody else in the classroom has a cell phone, it makes it a whole lot easier for your child not to have a cellphone," Pike said.

"If your child is the only one without a smartphone, that may present a whole additional set of stressors for your child," she added.

Phone-based childhood versus play-based childhood

Children who don't have a smartphone will need to replace that behavior with other forms of entertainment, the experts said.

"As this new phone-based childhood has come in, we've taken away what we call the play-based childhood, where kids used to have much more time being independent outdoors, playing, taking risks, and that is really crucial for human development," Rausch explained.

He said it's not enough to just remove the technology, parents have to give your child a new outlet for creativity.

One idea includes forming a group of parents who organize play dates at each other's houses every week where the children go outside and play while the parents stay indoors.

For teenagers, this can involve organizing social hangouts with friends like going out for a pizza.  

"It can be small, little, independent adventures outside of the home, and it's going to depend location by location of what is possible out there — going to a concert, going to the movies," he said.

"The goal is to have independence, and to be with other kids in person navigating social situations, navigating life out in the real world on their own, so that they develop the autonomy and the competency that they need to thrive," he added.

Start the conversation early

Pike and Rausch advise starting the conversation around smartphones from childhood so that your child isn't surprised later on.

"That conversation ideally should start early rather than suddenly," Rausch said, explaining that it will be harder to separate a child from a smartphone if they don't understand their parent's motivations.

He pointed to one book called "Kids' Brains & Screens" by Melanie Hempe which explains the risks and dangers of technology for a teen audience. Such a book could help start the conversation.

Pike said that even making a habit of giving a bored child a smartphone as entertainment can become a major issue down the line.

"It is easier if you've got a restless child at a dinner table, to put a smartphone in front of them to watch some cartoons, it will probably settle them down... if that becomes the default solution, then what parents need to understand is their kids aren't developing the skills of learning what to do with their boredom," she said.

"They're not learning how to sit quietly and imagine. They're not learning how to live with their curiosity, or create space where they can feel curious about something and go out and explore. They're not getting up and moving."

Model responsible smartphone use

Children learn from their parents so it's important to "model good behavior with our own phones" to show them what responsible smartphone use looks like, according to Rausch.

"Focus on what you can control and part of that is trying to model yourself as using technology well as a parent. So it's keeping your own phone out of the bedroom at night — that's something kids can see. Or during dinner, keep the phones away," he said.

Set strong boundaries

Your child or teen will likely have a tantrum or put up a fuss about not being given a smartphone — it's hardly a conversation that will go smoothly — but it's important to not give into their demands, Rausch said.

He asked whether a parent would give their child cigarettes or alcohol if they asked. If the answer is no, then the same logic must be applied to smartphone use.

"We need parents to have strong leadership and feel confident in saying no and it can be very hard to set those boundaries," Rausch said.

"But it's just like any other product that has a high risk of harming them, whether it's alcohol or cigarettes. The conflict is probably going to happen, but as a parent, we have the responsibility and the courage to just say no and to delay, and to explain some of the harms," he added.