Find the link I sent you before. Try it again, it's working now.

Hi Felix,

Media burner & Better Tube are the same app, you can just buy it once(from AppStore) with one apple ID. You can buy it twice only if you use another apple ID.
Better Tube Pro is another app, it needs to be purchased via PayPal(not AppStore), it also won't purchase you twice.

FAQs

Q: Why the BetterTube (installed from the AppStore) can not download videos?
A: Apple cut off the download functionality from it. Apple does not allow the app to download YouTube videos anymore. I did build a version with download functionality, but it was rejected when submitted to AppStore. Also, there should be no other apps on AppStore can do it.

Q: I have purchased Media Burner before, why I still need to purchase the BetterTube Pro?
A: I do want to provide it for free, but the new way to distribute BetterTube Pro is a lightweight service, it cannot carry too much users otherwise it will be shut down, so it can't be free. If you do need it, please purchase it.

Make sure you restore previous purchases with the Apple ID which you use it to purchased before.

Update now, the restore button is back.

The restore button is coming back, please wait.

In spite of no option for downloading, the new Better Tube still supports lots of features that the offical YouTube app does not support: background playing, remote control, queue songs without to create a playlist, etc.

Apple doesn't approve the full features(with download feature) app, I had to compromise, I'm sorry for that.
I'm still trying to find another way instead of AppStore to publish the full features app, if it's ready, I will post it on in the BetterTube.

Make sure your screen is unlocked, then rotate your iPad to landscape when playing videos.

Click the Home button, swipe down on the screen, search "better", you will see the icon.