Why browser extensions cannot block native iPhone apps

A Safari extension can change a website you open in Safari. It cannot change the separate YouTube, Instagram, Facebook, or TikTok app installed on your iPhone or iPad.

Why this matters

Safari and an app from the App Store are different applications with separate boundaries. When you open youtube.com or instagram.com in Safari, Still can run as a Safari extension on that website. When you open the native YouTube or Instagram app, Safari is not involved, so the extension cannot change what the app shows.

What Still supports

Still Free: removes YouTube Shorts in Safari.
Still Pro: removes Instagram and Facebook Reels, blocks the TikTok website, and syncs settings across supported surfaces after sign-in.

Still does not claim to block short-form video in native social-media apps.

Turn it on in Safari

Install Still from the App Store.
With iOS 18 or later, go to Settings → Apps → Safari → Extensions → Still. With iOS 17 or earlier, go to Settings → Safari → Extensions → Still.
Turn on Still and allow the websites you want it to change: YouTube, Instagram, TikTok, and Facebook.
Open those websites in Safari and reload after changing permissions or a Still setting.

Visit Support for setup, troubleshooting, purchases, and restore help.