The site codekiem.com has released an extension for the Google Chrome browser on PC called APK Downloader that allows you to download the APK installations files directly to your PC.
Of course, this Google Chrome extension only allows you to download free applications or payed ones that you have actually bought and this is not, in any way, a way of piracy. You can check in this video how easy is to download the files once you have installed this.
In order to get this extension working, including the installation file, you need to make some changes on your browser. To get all the steps on how to get the APK Downloader working, you should visit the link.