A few years ago, Instagram launched a new feature that allowed users to zoom in on photos, and the feature also applied to videos, allowing users to zoom into specific parts of a video that they wanted to see more clearly.
The zoom feature does not exist on YouTube, but that could change in the future. It appears that the company is working on an experimental feature that would allow users to zoom in on specific parts of a video.
At the moment, the closest thing to zoom on YouTube would be pinching the screen, but that basically only allows a video to fill up the entire area of your phone’s display so that there aren’t any weird black bars, so while technically that is zooming in, it’s not by much and users have no further control over it.
Right now, this zoom-in feature, which is still experimental, is exclusive to YouTube Premium subscribers. Premium subscribers will be able to opt-in on it and give their feedback to Google before the feature is released for everyone, if they decide to do that at all. We’re not sure in the future it could remain a Premium-exclusive, but that’s just something we’ll have to wait and see.
Source: Android Police