I can't install YouTube on my iPad mini ios 9

Yup.

Your iPad is too old to use the YouTube app, now!

You will need to use one of these third party Web browsers to use the actual Desktop version of the YouTube Website, instead.

That over 3-year old Safari Web browser will no longer stream YouTube from main YouTube Website.

STOP using that nearly 3-year old Safari web browser, as it is, probably, not safe and secure to use any longer, and seek out a third party web browser that is STILL currently being updated and STILL being supported on iOS 9.3.5.

Here are a few third party web browsers that I know are STILL being updated and supported on iOS 9.

Available and more popular third party Web browser choices are dwindling faster, now.

There are still a handful of iOS 9 and earlier supported third party Web browsers.

Some of these have had recent updates, too!

Here’s what’s left.

iCab Mobile Web browser

Aloha Web browser

Dolphin Web browser

Snow Bunny Web browser

Maxthon Web browser

Private Browsing Web browser by Savvy Soda

Private Browser Deluxe

TOR browser anonymous

Turbo VPN browser

TOR + VPN web browser private

Some or most of these third party Wen browsers should still be able to access the YouTube Website.

Good Luck to You!