Android users experiencing unexpected ads after phone calls are encountering a form of ad fraud linked to applications on the Google Play Store that utilize a tactic called AfterCall. These applications, often benign utility apps, request overlay permissions to display ads over the Android interface. They can launch full-screen advertisements disguised as call information screens after detecting the end of a call. Overlay permissions are categorized as "special permissions" and require users to enable them in system settings, rather than through typical installation pop-ups. Users are advised to check for apps with overlay permissions by navigating to Settings > Apps > Special app access and uninstall any unfamiliar applications. Regular audits of these permissions are recommended to disable unnecessary ones. While these apps primarily serve as an annoyance, they can waste advertising dollars and potentially harm brand reputations.