Google removed the Parler app (a Twitter alternative) from the Play Store shortly after it saw record traffic due to Twitter banning Trump. A spokesperson for Google gave the following statement:
In order to protect user safety on Google Play, our longstanding policies require that apps displaying user-generated content have moderation policies and enforcement that removes egregious content like posts that incite violence. All developers agree to these terms and we have reminded Parler of this clear policy in recent months. We’re aware of continued posting in the Parler app that seeks to incite ongoing violence in the US. We recognize that there can be reasonable debate about content policies and that it can be difficult for apps to immediately remove all violative content, but 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.
The very next day, Apple followed suit by removing Parler from Apple’s App Store, and Amazon disabled Parler’s servers on Amazon Web Services (AWS).