The decision that matters isn't which phone. It's what's on it, and where it sleeps. Set it up before you hand it over and it's about an hour, once. Try to add rules to a phone your kid already thinks of as theirs, and it's a fight.
Turn on Apple Screen Time on an iPhone, or Google Family Link on Android. Set quiet hours, turn on content limits, and make new app downloads need your OK. Then set a passcode your kid doesn't know. Skip that and they can undo all of it in about a minute.
On Android? Google Family Link does the same job. I don't have a step-by-step guide for it yet.
The phone is just how the apps get in. The apps are where the chats, the feeds and the late nights happen. Decide which ones go on before you hand it over, and install them yourself. Then lock it so nothing new goes on without your OK. You do that in Screen Time: block app downloads, and hide or limit the apps you don't want. Where an app has its own settings, turn them on too: chat off or friends only, and the content level set for their age.
If they game, games have their own chat and spending controls, and those live inside each game or console:
Give your kid a profile on your home router, so websites, apps and a bedtime are set once for every device in the house. I recommend the TP-Link Deco BE65, because it's the model confirmed to block apps. Some cheaper Decos that look almost the same only block websites. No router yet? Start free tonight with the CIRA Canadian Shield filter, about 10 minutes.
Agree where the phone charges overnight: anywhere but the bedroom. Write it down and put it on the fridge. When the WiFi goes off at bedtime, it's the house's rule, not another argument with you.
Setting it up is half of it. Once a week, look at the Screen Time report on your phone and the activity in your Deco app. You're looking for anything new: an app you didn't expect, use late at night, a site that keeps getting blocked. It's how you find out about something early, before it turns into a crisis.
No setup is a force field, and I'd be wary of anyone who sells it that way. What it does is real: sites and apps they shouldn't be on don't load, the phone goes quiet at bedtime, and you're not the one saying no every night, the router is. It's made a huge difference in our house. What it can't see is a phone on cellular data, or someone messaging them inside a game you've allowed. That's why the app settings and the conversation matter as much as the router.
Every tap, with a screenshot. No sign-up for the guides themselves.
Stuck on a step? Email me at colin@safefamilyinternet.ca.