Here are the step-by-step instructions to install Downloader on your FireStick via the Amazon App Store:

1. Click the Find icon on your FireStick home.

2. Select the Search box.

3. Using your FireStick remote, type Downloader using the on-screen keyboard. Then, select the first Downloader suggestion.

Note: If you have a FireStick remote that supports voice control, press and hold the Microphone icon and say “Downloader.”

4. Open Downloader.

5. Click Get/Download on the Downloader’s dashboard. After a few seconds, the Downloader will be installed.

Now, you can access Downloader from the Your Apps & Channels section.

How to Prepare FireStick to Use Downloader and Sideload Apps

By default, FireStick does not allow the installation of third-party apps. Therefore, you must first change this setting to enable sideloading. Please follow these steps:

1. Launch your FireStick home screen and navigate to the Settings icon.

2. Scroll down to the My Fire TV tile in the bottom left corner and click on it.

3. Click on Developer Options.

Note: If you do not see Developer Options, go to Settings > My Fire TV> About.
Now, select Fire TV Stick and click it 7 times to enable Developer Options. 

4. You will see one of the following two options depending on your FireStick device version:

• Option 1—Install Unknown Apps: Click it and proceed to the next step to enable Downloader.
• Option 2—Apps from Unknown Sources: Click this option and then click Turn On at the following prompt. Skip the next step.

5. Navigate to Downloader and select it to turn it ON.

Note: This window will not appear if your device displays Option 2 in the previous step.