Easiest way is via the downloader app.

If you have it already on an Android phone then apps2fire apk will install it direct from your phone

Sideload (google is your friend)

Many ways mate, you can use downloader, es file manager, Aptoide, etc. Why you are so lazy with Google?

I did it a few days ago, used Aptoide.

you can use smart stb easily bro

i found good tutorial here https://geniusiptv.com/how-to-install-and-set-up-perfect-player-on-android-phone-android-box-android-tv-v2-amazon-fire-tvstick/

Turbostreams.org free 24 hr trials

If you have an actual .apk file (such as website.com/blahblah.apk ) you could download it directly with "Downloader". Downloader comes up in the Amazon App Store...install that and just type in the URL to the APK and install (assuming you have 'allow from unknown sources' checked in firestick settings).

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