How to Sideload Apps on Amazon Fire Phone: This Guide is Useful for Both Amazon Fire Phone (Unlocked GSM) and Amazon Fire Phone (AT&T) (Newbie to Pro! Series)

Fire OS is a forked version of Android OS and you will need some tweaks to be able to install those applications that will easily get installed on Android OS. In addition, Amazon app store is somewhat limited when compared to app store like Google play store. This booklet provides clear steps on how to go about the installation of third parties applications on your Amazon Fire Phone. It also tells you how to install Google play store and many other apps.
Note: Some of the content of this booklet is also contained in my book on Amazon Fire Phone titled Amazon Fire Phone: The A-Z Guide, but this booklet provides much more information about sideloading apps on Amazon Fire Phone. I will therefore advise that you get a copy of this booklet if you are thinking of learning new things about sideloading apps on Amazon Fire Phone. However, if you are looking for more detailed and robust guide on Amazon Fire Phone, then getting a copy of Amazon Fire Phone: The A-Z Guide will be a better option.
Finally, this guide is useful for both Amazon Fire Phone (Unlocked GSM) and Amazon Fire Phone (AT&T) 
The chapters covered in this guide are listed below:
Tackling the Problem of Limited Apps in Amazon App Store
How to Sideload an app on Amazon Fire Phone
How to Download Apk of Different Apps of Your Choice
How to Sideload Google Play Store on Amazon Fire Phone (Unlocked GSM)
Top Apps to Consider For Sideloading