Apple may have altered its guidelines for marketing violent games in the App Store, as reviewers are reportedly rejecting some games that have guns or show human violence in their screenshots or app icons.

Multiple game developers have been forced to alter their games' App Store promotional materials to remove images of guns and violence, according to PocketGamer. Among those that ran afoul of the new criteria was Splash Damage's recently-released Tempo, which now features guns censored via pixelation in its screenshots.

Pascal Bestebroer, the developer behind pixel-art shooter Gunslugs 2 — Â which initially suffered a rejection, but was later accepted without any changes — Â told Kotaku that he believes Apple is worried about cleaning up areas of the App Store which are not behind an age gate.

"The idea behind it, from what I understand, is that even tho the app has a 12+ rating, they do need icons and screenshots and basically the store-page to be 4+ rated," he wrote. "So screenshots should not show anything that is below the 12+ rating.. which is a bit hard to do for most action games."

If Apple has altered its criteria, the new standards are not being applied evenly. Playdemic's Gang Nations, last updated on Wednesday, shows cartoon gang members pointing revolvers at each other, for instance.