Nowdays, it's pretty simple to run APK files in an emulator environment. For this purpose, Bluestacks is the right software. The software installs as any application and it successfully emulates Android 4.x. It even assigns file association to APK files. When you double click an APK it automatically installs in Bluestacks. However, even if Bluestacks is recommended, you could also try You Wave. It demands few resources to run but it's shareware.
Another solution is Genymotion. It's free for personal use.