To turn on apps from unknown sources on your Firestick 4K Max, follow these steps:
- From the Firestick home screen, navigate to Settings (gear icon).
- Select My Fire TV.
- If you do not see Developer Options , you need to enable it first:
- Go to About.
- Highlight your Fire TV device name (e.g., Fire TV Stick 4K Max) and press the Select button on your remote 7 times until you see a message that developer options are enabled.
- Go back to My Fire TV , then select Developer Options.
- Tap on Apps from Unknown Sources and enable it.
- Optionally, install the Downloader app from the Amazon Appstore to help download and install apps from unknown sources.
This will allow you to install third-party apps that are not available in the Amazon Appstore