Get the app on your Fire Stick, Android TV, or any Android device.
Go to Settings → My Fire TV → Developer Options → Install Unknown Apps → Turn ON for your browser (Silk or Firefox)
Open the Silk browser on your Fire Stick and go to:
tvcentral.us/download
Tap the Download button above.
Once downloaded, tap the notification or go to your Downloads folder and tap the APK file. Click "Install" when prompted.
Open TvCentral, enter your username and password (from your subscription), add your IPTV servers, and enjoy!
Install "Downloader" from the Amazon App Store. Open it and enter this URL:
tvcentral.us/api/download/latest
If your Fire Stick is on the same WiFi as your PC:
adb connect YOUR_FIRESTICK_IP:5555
adb install -r TvCentral.apk
Download the APK on your computer, copy it to a USB flash drive, plug it into your Fire Stick, and use a file manager app to install it.