By deeply customizing AOSP, manufacturers not only gain precise control over user and app activities but can even manipulate and interfere with user choices. Thus, manufacturers optimize the user experience of their own app stores while deliberately making other download methods more difficult, subtly funneling user traffic to maximize their profits. On this brand’s smartphones, some apps exhibited highly unusual behavior: When a user tapped an app icon on the home screen, instead of being taken to the app’s homepage after the splash screen, they were redirected to an ad-filled page.