As noted by MacRumors, Apple has notified its iOS developers that future app updates and submissions are now required to include screenshots that meet Retina resolution specifications.
The requirement applies to both iPhone and iPod touch developers, and it looks like Apple won’t be approving apps that don’t qualify…
In its message to developers, Apple writes:
“Required iPhone & iPod touch Screenshot Upgrade for Retina Display
When you create or update your apps in iTunes Connect, you must upload screenshots that are high-resolution. We require your screenshots as high-resolution images so that your app is optimized for the Retina display.
The requirements for high-resolution images are 960 x 640, 960 x 600, 640 x 960, or 640 x 920 pixels. Images must be at least 72 dpi, in the RGB color space, and the file must be .jpeg, .jpg, .tif, or .png. You can update your screenshot files at any time in iTunes Connect.”
The move makes sense, considering Retina display-equipped devices have been on the market since 2010.