Apple is testing a new design for App Store search ads on iPhone. Some users on iOS 26.3 are noticing that the blue background around sponsored results is no longer shown, blurring the line between what paid ad results look like and the real search results that follow.
This means the only differentiator between organic results and the promoted ad is the presence of the small ‘Ad’ banner next to the app icon. Right now, it appears to be in some kind of A/B test phase.