Yes, once the Bluestacks application has been installed on your PC, the APK format has been associated with the Bluestacks APK installer which means the next time you double click an APK file, it will be installed inside the Bluestacks (Android) environment. If the application is compatible with the version installed, the you will see it in the Applications list ready to be launched. Use the magnifying glass to look for applications inside Bluestacks.