To help you get the best setup for your vintage device, could you let me know:

[Discussion] Working YouTube on iOS 9.3.5 : r/LegacyJailbreak

Generate a personal via the Google Developer Console (free).

If you prefer not to jailbreak, you can still watch YouTube through the Safari browser, though it may be slow.

Launch Filza and navigate to the root directory by tapping the back arrow until you see a single forward slash ( / ).

Completely close the YouTube app from your multitasking switcher if it was open in the background. Launch the YouTube app from your home screen.

Tap on your under the Developer App section.

Step 4: Fix the "Update Required" Error (The Plist Modification)

To fix the YouTube app on iOS 9.3.5, you typically need to bypass the "Update Required" or "Error Loading" messages caused by the app no longer being supported on older software Option 1: Official App Store Method (No Jailbreak)

Sideloadly (recommended) or AltServer/AltStore.

Step 3: The Critical Fix (Bypassing the "Update Required" Error)

installed on your computer (e.g., Sideloadly or AltStore). Sideloadly is highly recommended for iOS 9.

If you prefer not to edit files manually, some legacy jailbreak repositories host tweaks that automate this process.

If you are reading this, you likely own a vintage Apple device stuck on iOS 9.3.5. For these devices (A5 and A6X chips), iOS 10 is impossible, and iOS 9 is the end of the road. For years, users of the iPhone 4s and iPad 2 have faced a frustrating reality:

If Sideloadly throws a login error, ensure you have the official version of iTunes installed on your computer (downloaded directly from Apple’s website, not the Microsoft Store). Alternative Method: Browser-Based Playback

This has led many users to search for the phrase — a quest for a modified or older YouTube IPA (iOS App package) that can be sideloaded onto these vintage devices.