One awesome tweak that you can get for a jailbroken iPhone is YouTube ++, but the best alternative for a non-jailbroken iPhone is ProTube.
ProTube allows you to watch YouTube videos without ads and even provides you with the opportunity to play videos in the background without the video part playing.
These are features that are normally only available to YouTube Red subscribers, but ProTube offers the capabilities within its app.
It's $2.99 and you have to watch YouTube videos within the app to get the features, but it's worth it.
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