Yeah forget that. At first I thought it was a joke of some sort. But I guess that's how you are supposed to do it.
I'll just stick to Netflix and watch videos there. Somehow that manages to work without side-loading a bunch of crap.
It's half google's fault for not allowing the amazon store app to be listen in Play.
Oh you want to make a youtube player that acts like every browser in the world, with the ability to minimize? Banned.
(The most sensible-sounding negative claim I've heard is that Amazon do that so that they can do more invasive location tracking than Google permits (though the same kind that Google does themselves))
* It annoys me as a consumer.
* It reeks of incomptency ( yeah, go and disable that security check that looks like it is there to prevent malicious software to be installed on your device, yeah, yeah, that one ).
* It is a convoluted process.
* It leaves my device vulnerable. Let's not speculate (like you did apparently) but copy and paste from their own source:
https://www.amazon.com/gp/feature.html?ie=UTF8&docId=1003016...
---
Update Phone Settings
Go to your phone Settings page
Tap Security or Applications (varies with device)
Check the Unknown Sources box
Confirm with OK
Step 2
Go to Downloads Open Downloads on your device by going to My Files or Files
Tap on the Amazon App file (Amazon_App.apk)
Tap Install when prompted
Step 3
Launch Underground App Tap Open to launch the Amazon Underground App
Use the Menu on the left and select Apps & Games
---Yeah, I don't see anything about the "untick the checkbox again" part.