Apple and Alphabet have raised concerns about Amazon's content moderation policies after learning that sexually explicit photographs could be accessed by children on a popular Kindle app. The explicit content at issue is primarily self-published through Amazon's Kindle Direct Publishing arm, through which authors can self-publish their books nearly instantaneously through Amazon and designate the content as available for the Kindle Unlimited service. Amazon's terms for its self-publishing arm mention that content could be rejected for publication if it is 'offensive or inappropriate' or 'contains pornography.'

Apple and Alphabet stated that their concerns were around policy violations but did not provide details of how their rules were broken or their conversations on the matter with Amazon. The companies can, at their discretion, remove an app from their app store for rules violations or other reasons. They had done so in the past when apps included pornographic material.