New York- The only consensus among parents about the right age for a child to have unfettered access to a smartphone is that there is no magic number.

But if you sign up for Family Link, which is Google’s new parental controls software for managing children’s Android phones, Google decides for you. At the age of 13, a child can choose to “graduate,” as Google calls it, or lift restrictions, getting the keys to the internet kingdom and all the good and bad things that come with it.

That’s too bad, because at first glance, Family Link has all the hallmarks of a winner. It is free, well designed and packed with thoughtful features for regulating a child’s smartphone use, like the ability to monitor how often a game is played or even to lock down a device during bedtime.

Yet nearly all of those benefits are undermined by Google’s decision to let children remove the restrictions the instant they become teenagers.

“The fact that the kid can graduate themselves is just preposterous,” said Jesse Weinberger, an internet safety speaker who gives presentations to parents, schools and law enforcement officials. “It takes the power out of the parents’ hands, which is a big no-no.”

Google made Family Link available for public testing in March, though the software is still in development and available for use on an invitation-only basis. Before it goes wide, I tested the parental controls for a week and assessed the features and policies with child safety experts.

The takeaway: If you are contemplating the purchase of an Android phone for your child but want to restrict access, there are better parental apps out there that give you more control. Or you could buy your child an iPhone, which has restrictions that can’t easily be removed.

An Overview

Family Link has lots of perks that may be a boon for parents. To set it up, request an invitation to the program on Google’s webpage and wait for an email with a link to install the software. The app is available for both iPhones and Android devices.

Inside the app, you can create Google accounts for your children, sharing information like their names and birth dates. Then when your child logs in to an Android phone, the device immediately requires you, the parent, to log in and install the Family Link app onto the device so it can be monitored.

From there, Family Link is a breeze to use. On the parent’s phone, tapping on the child’s account profile brings up a list of options. You can follow a child’s location, which can be useful for safety purposes or for picking the child up from school. You can also approve or reject apps that a child is trying to download — so if you’re reluctant about Snapchat or an addictive game like Boom Beach, simply block the apps. Parents can also get a weekly report to see how often a child is using a certain app, like a game, and choose to have a conversation with the child about using the software responsibly, or block the app temporarily.

Parents can also use Family Link to create restrictions for how children browse the web. You can turn on a filter that blocks mature websites, though Google acknowledges the filter is imperfect and some offensive sites may get past it. For a more nitpicky approach, you can also require the child to get permission for each site visited, blocking the ones you disapprove of.

Parents will probably love a feature called screen time, which can be used to set limits for how long a child can use a phone each day. For instance, you could give the child three hours of screen time on weekdays. You can also schedule regular bedtime hours that lock down the device at specific times — between 9 p.m. and 7 a.m., for example. Before the device is about to be locked, the child gets a notification; when the screen locks down, the child will still be able to answer phone calls to talk to the parent or tap on an Emergency button to call the police.

Caroline Knorr, the parenting editor of Common Sense Media, which evaluates content and products for families, applauded the screen time feature, noting the difficulty of getting children to put down their phones. But she said sticking with time limits and schedules would be complicated. A child may not be done using a device to work on a science report by the time the screen locks down at 9 p.m., at which point the parent would have to manually unlock the device, she said.

“It’s not a set-it-and-forget-it thing where parents think, ‘Oh, great, this is going to solve all my problems,’” she said. “We’re all still learning this technology, and life is very unpredictable.”

Why 13?

All these neat parental controls start to come undone the day the child turns 13. At that point, Google gives the child the option to be free of the Family Link restrictions or stick with them — and I can’t imagine any child choosing the latter.

Saurabh Sharma, Google’s product manager for Family Link, said the policy was designed this way because 13 is when people can register for Google accounts without parental consent. That complies with a federal regulation in the Children’s Online Privacy Protection Act, which forbids companies from collecting data from children under 13 without a parent’s approval.

Yet I would argue that Google should design a policy with parents’ best interests in mind. It could let the parent decide when the child has demonstrated safe, responsible smartphone use and graduate from all restrictions. That might happen when the child turns 13, 15 or even 17. But the children should not be allowed to strip away settings just because they turn 13.

“It’s hard for me to understand why a parent would give a kid a phone and then turn off all the features through the app and then grant them all the features once they turn 13,” said Ms. Knorr of Common Sense Media. She said the age of 13 was related purely to the federal regulation, not safety or childhood development guidelines.

By comparison, Apple’s iPhone includes restrictions like limiting adult content on websites, turning off in-app purchases and preventing a child from burning through your cellular plans. The restrictions can be changed or removed only with the correct passcode set by the parent — it doesn’t matter how old the child is.

Google’s Mr. Sharma said Family Link was still in testing and the company was continuing to collect feedback from parents on issues including the age policy.

“This is a tricky subject,” he said. “It’s hard to figure out what works for every family.”

Bottom Line

If you agree that your child should get unrestricted access to a smartphone at the age of 13, Family Link is an excellent product. But how can parents ever predict that?

Ms. Weinberger, the internet safety expert, said she had heard stories from parents and children about a 9-year-old addicted to pornography, a fourth grader being “sextorted” by a 13-year-old, and child predators stalking minors through social networking apps. In other words, any child is subject to danger, no matter how old.

For Android users, Ms. Weinberger highlighted a parental control product called Qustodio, which lets parents monitor their children’s text messages, disable apps at certain times of day or even shut off a smartphone remotely — restrictions that don’t vanish the day a child becomes a teenager.

She called Family Link “depressing” because of the age policy.

“We want our kids to have some access and we want to be able to decide,” she said. “We need for Google in particular to be the leader on this.”

The New York Times