As I said, the app is not available on Amazon Store. You have to install it on your FireStick as a third-party app using Downloader.
Now follow these steps:
Step 1: Open Firestick Home
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Step 2: Click on the Settings icon
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Step 3: Select My Fire TV
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Step 4: Choose Developer Options
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Step 5: Click on Apps from Unknown Sources
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Step 6: Click on Turn On
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Step 7: Navigate back to the home page and select the Find menu
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Step 8: Click on the Search option
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Step 9: Type “Downloader” and select it from the list
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Step 10: Select the Downloader icon
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Step 11: Click on “Download” and wait for the app to install
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Step 12: Wait until the download is completed
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Step 13: Click on Open to run the Downloader app
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Step 14: Once the downloader opens, click on Allow
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Step 15: A prompt will be displayed, click OK
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Step 16: By default Home tab would be open with a text box displayed on the right side
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Step 17: Enter the URL “bit.ly/xciptv-2” in the URL bar and click GO. This link is V.5.0.1 apk which is the latest version of XCIPTV.
Note: The referenced link is the official URL of this app/website. FIRESTICKHACKS do not own, operate, or re-sell any app, streaming site, or service and has no affiliation with its developers.
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Step 18: Wait for the app to be downloaded
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Step 19: Click the Install option
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Step 20: Click Done or Open once the app is installed
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Congratulations! The XCIPTV app is now successfully installed on your device.