An update to the YouTube app introduces in-video suggestions about what to watch next. The banner ads are super-imposed over the video you're watching. The suggestion can be dismissed by tapping an 'X' that appears next to the text. Google calls this InVideo Programming, and it is pretty easy for content creators to access.
The feature first appeared on YouTube last year. The suggestions are triggered by video producers to allow them to get viewers to explore other clips from the same source.
This latest version of YouTube also features closed captions for live streams and the usual stability improvements.