What is a letterboxed video or image?
A letterboxed video or image is one that has black bars or borders at the top and bottom of the screen or image.
Pillarboxing is the term used to describe the effect when black bars appear on the left and right sides of a video or image.
This is done to preserve the original aspect ratio of the content when it is displayed on a screen or device with a different aspect ratio.
For example, a widescreen movie may have black bars at the top and bottom when it is displayed on a standard 4:3 television or a vertical image may have black bars on the sides when displayed horizontally.
In other words, the video's dimensions are taller and narrower than the screen's dimensions. To fit the video on the screen without distorting the image or cropping out important content, the bars are added on either side to fill the remaining space. The same applies to images that have a vertical orientation, resulting in bars on the top and bottom instead.
Will app stores reject my app if my content is letterboxed?
According to the Google Play Store policies, letterboxing can be used to provide a consistent viewing experience across different device aspect ratios. However, excessive letterboxing may not be allowed if it significantly impacts the user experience or if it doesn't comply with the platform's policies.
Some tips
Letterboxing is allowed to maintain aspect ratio consistency.
The letterboxing should not be excessive to the point where it significantly impacts the user experience.
The letterboxing should not violate the platform's policies, such as obscuring important parts of the content or user interface.
In our experience,
Content that is letterboxed (top and bottom bars) passes through unless they are hindering the viewing experience, but pillar boxed (left and right bars) are rejected more frequently
 16x9 content | perfectly acceptable |
 wider content adapted to 16x9. This mostly happens when 4x3 videos are converted to 16x9 | Accepted when the bars are not hindering the viewing experience. |
 narrower videos fitted to 16x9 | We've seen some of these cases being rejected. |
 smaller aspect ratio made to fit a 16x9 screen | Rejected in most cases |