Owners of the two biggest mobile app stores took action on Friday against the Parer social networking service because of posts inciting violence, with Alphabet Inc's Google removing it and Apple Inc warning it may do the same.
Google said the app favoured by many supporters of US President Donald Trump must demonstrate "robust" content moderation if it wants to get back in the store. Apple gave the service 24 hours to submit a detailed moderation plan, pointing to participants using the service to coordinate Wednesday's siege of the US Capitol building.
The actions by the two Silicon Valley companies mean that the network seen as a haven for people expelled from Twitter could become unavailable for new downloads on the world's main mobile phone app stores within a day. It would still be available in mobile browsers.
Parler Chief Executive John Matze said in posts on his service on Friday that Apple was applying standards to Parler that it did not apply to itself and the companies were attacking civil liberties. He added in a text message to Reuters, "Coordinating riots, violence and rebellions has no place on social media."
In suspending the service, Google, whose software powers Android phones, cited its policy against apps that promote violence and gave recent examples from Parler, including a Friday post that began "How do we take back our country? About 20 or so coordinated hits" and another promoting a "Million Militia March" on Washington.
In a statement, Google said that "for us to distribute an app through Google Play, we do require that apps implement robust moderation for egregious content. In light of this ongoing and urgent public safety threat, we are suspending the app’s listings from the Play Store until it addresses these issues."
In a letter from Apple's App Store review team to Parler seen by Reuters, Apple cited participants of the mob storming the US Capitol building on Wednesday.
"Content that threatens the well-being of others or is intended to incite violence or other lawless acts has never been acceptable on the App Store," Apple said in the letter.
Apple gave Parler 24 hours to "remove all objectionable content from your app ... as well as any content referring to harm to people or attacks on government facilities now or at any future date." The company also demanded that Parler submit a written plan "to moderate and filter this content" from the app.
Apple declined to comment.