Karl-Heinz Fogarascher has spotted a new visual effect in Google Search ads on iPhone using Chrome. In this test, static image assets smoothly slide into the ad copy, creating an animated transition between visual and text elements.

This appears to be part of a UX experiment by Google aimed at boosting engagement and increasing click-through rates, by making the ad more eye stopping. See it for yourself:
While animation in ads isn’t new, integrating motion directly into the static ad experience could signal a move toward more interactive formats in standard search placements.
No official documentation has been released yet, and it’s unclear how widely this test is being rolled out.