My thinking (often flawed) is that as an iPhone user, if I could buy an iPhone or a Fire Phone for the same price, there's no way I'm going with a Fire Phone just for one of these features.

If, however, I was an Android user, I would consider buying the Fire Phone as a replacement device, along with similar phones like the Samsung Galaxy.

You can sum up Google and Apple's market positioning in a tweet if you wanted. (Apple: premium phones, premium prices. Google: give away the software, monetize the search.) Amazon's positioning here is more vague, or perhaps nuanced.