Have app update, but not features

On some apps I have downloaded the most recent version, but don’t get the features of the app. For example, I have the most recent version of YouTube, but not the new change to the interface. When swiping down on a video, mine still becomes a little box in the bottom corner, whereas my friends who have the update have a bar across the bottom that lets them pause without having to pull up the video. This also happens for some other apps as well. I am on the newest iOS update.