It's an ad on your lock screen, which you can either swipe away or tap to view.
Or, if notifications salt the screen, the ad will shrink to banner size.
Amazon also preloads apps on the home page. You can sign in to them all in one fell swoop when you set up the phone (or not!)
You can delete these apps and customize the home screen any way you'd like.
Amazon will eventually target ads to your buying and browsing patterns, but I'm not sure why it thinks I'm interested in whey protein.
A second ad module appears as a home screen widget.
You can drag and drop to delete it.
Double-tap a notification-style ad to open it.
Here's what you'll see if you tap it once (like on accident, for instance).
Opening an ad kicks off the corresponding Amazon app or website.
In this case, it's Amazon Prime's video collection. You can tap to stream now.
Apart from the two sizes of lock screen ads, the phone looks and acts just the same as the full-price Moto G4.