I have a few Windows Phone apps in the store and each of my apps has a "More apps" part where I promote all of them. Is it possible to know if they installed one of my apps so I don't show it in the list anymore?
Try InstallationManager.FindPackagesForCurrentPublisher: Returns all the app packages with the same publisher ID as the app calling this method, details at https://msdn.microsoft.com/library/windows/apps/windows.phone.management.deployment.installationmanager.findpackagesforcurrentpublisher(v=vs.105).aspx