To install applications from third party developers, you need to enable a feature in Firestick called "Application Installation from Unknown Sources" and we already have a tutorial for it. Recently Amazon decided to hide this feature. Here I will show you how to unhide it.

 

1-From dashboard, click on gear icon which is Settings.

 

2-Scroll down a bit and select My Fire TV.

 

3-Select About.

 

4-move on to Fire TV Stick and press OK button 7 times. While taking the above picture, I pressed 5 times already to at the button it is asking me to press 2 times more.

 

5-When pressed enough, It confirms the activation of Developer mode. Click back button to go to the previous page.

 

6-You can now see that Developer Options has appeared.

 

7-You can now click install unknown apps to enable application installation from unknown sources on your Fire Tv Stick.

 

Any questions? post it on WDS Community Forum and let us help you.