Why the Poster Frame is important
As the poster frame takes the first spot in the screenshot gallery, it is visible not only on the product page but also on SERPs. Thus, it has great potential to attract the attention of potential users.
For this reason, it should be well designed, informative, and relevant to the app. If no frame of the app preview video matches these criteria, app owners should create a static creative and add it as the first frame to the video.
When appearing in the gallery, a play button overlays the poster frame. Thus, it should not contain any crucial components like a logo in its center (see the example by Tandem which is a bad example in this context).
The Google Play Feature Graphic
On Google Play, app owners have to upload a feature graphic. In contrast to iOS, it is not part of the video. Instead, it is a separated static graphic of 1024×500 pixels in landscape format.
It will appear next to the screenshots and link users to the promotion video.
Like the iOS poster frame, the feature graphic is overlayed by a play button. Therefore, app owners should follow the same design guidelines and not place relevant components in the center.
The example below shows the feature graphic of the game Fallout Shelter.