[mgz]

Just launched a restricted browser for kids for iOS: https://weblock.online Now testing on my kids. The idea is that the browser is whitelist-only, so kids can open only approved websites. I receive a notification when they want to visit an unknown website and I can allow or deny it. Works great for my family, hope it will be useful for someone else.

[TZubiri]

How does it work on a more technical level? I would be interested in seeing a bit more tech detail, perhaps because I'm more technical, but also there's so much competition in this space that you need something to differentiate.

For example, is the blocklist UX side Domain based? Company based (Allow all by Google/Alphabet), category based (Search engines)?

And on the backend, is it DNS based or HTTP based? Or maybe an OS hook.

[mgz]

Hey, more technical details follow.

Weblock uses a whitelist, not a blacklist, and it is domain based. Once you allow a domain, it can be browsed by a child. You can allow it forever/15 minutes/1 hour.

How it works: WKWebView, before loading a page, asks the backend if the domain is allowed. If not, it shows "Not allowed" screen and a "Request access" button - child can tap it and you (parent) will get a notification.

So traffic is not going through the backend or a filtering VPN, the app just asks the backend if a page (domain) is allowed to visit.

Visits are logged, so you, as a parent, can see what your child has been browsing. How much time did he spend on a homework website.

Some WKWebView callbacks used for that: * onShouldStartLoadWithRequest - to intercept a request and check if it's allowed * onLoadProgress - to show loading progress bar * onNavigationStateChange - to track browsing history

Also I had to implement a workaround for buggy Screen Time in iOS 26 - even if you add Weblock to "always allowed" apps, iOS will still treat each website as a separate "app" and block it, asking to you "allow' each website on system level. It happens inside WebKit codebase, but luckily this bug has another bug in it - if you re-open a website, it suddenly works and all other websites in this session work tooSo I need to listen to `onScreenTimeBlockingStateChange` event and automatically reload a website if that happens.

Also I added an ad blocker to Weblock. It uses uBlock Origin filters, converts them to WKWebView content rule JSON format and feeds to WKWebView. The app checks the backend if rules are updated and updates a local copy.

What's next: need to get "Default Browser" entitlement from Apple. Then you can block Safari on kid's phone using Screen Time and have Weblock open all HTTP(S) URLs.

App is written in React Native, no performance issues. Backend is Ruby on Rails.

[TZubiri]

Does it handle ancilliary domains correctly? For example if I allowlist youtube.com, but that also uses youtu.be or cdn.google.com, do resources from those domains get blocked until I specifically allow them?

[mgz]

Didn't get to this detail yet. What the app currently does is allow all resources but block the ones that come from any youtube domain (this will block youtube embeds). Currently this is enough for my kids.

Also I add some relaxing rules, eg: If you navigate to domain A and it redirects you to domain B, do not block B immediately, give it a couple of seconds. It may redirect you back to A and it just wanted to set a cookie on B.

I am adding some gift codes for those who want to check the app but not bother with trial/subscription:

* https://weblock.online/al/gift?code=438912467308

* https://weblock.online/al/gift?code=336293589225

* https://weblock.online/al/gift?code=021644422165

When Weblock asks you to subscribe, just open one of these links on the same phone and it will work for you for free.