http://www.blogsolute.com/download-android-apk-files-google-play-directly-to-windows-pc/26531
Real APK Leecher has a simple interface. Upon first run it will ask for your Google credentials. Additionally you have to give your mobile Device ID that you have obtained previously. If you have shared it to your mail, just copy and paste it on the given field. You can select the location to save downloaded apps. If you have more APK files, you can also view them in this app. Once you are over with it, you are good to go.

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