Here’s how you install Spotify on the Kindle Fire. This is a temporary mod that works flawlessly. Hopefully, the Amazon Store will eventually get their own version. Until then, this should work fine.
(Make sure to delete any previous Spotify app from your system before installing.)
Installation instructions:
1. After downloading the On your Kindle, go to settings > Device and turn “Allow Installation of Applications” on.
2. Download the attached modified .apk
*For some reason it will give an error if you try to install with the default installer on the Kindle Fire, so you can’t simply install it from the browser*
3. Download AndroXplorer for free from the Amazon App Store (or an equivalent such as File Expert).
4. Open AndroXplorer and browse to /sdcard/Download/
5. Tap KFSpotifyAndroid.apk and it will bring up a dialog asking you to install.
*You might have to restart your Fire before this will take effect if you have all already installed Spotify on your device*