--start rant--
Amazon is too aggressive in trying to bind customers to their ecosystem. Customers appreciate that much less than Amazon's managers might think. Case in point: Because Google for inexplicable reasons did not let me buy anything with my well-working Paypal account, I had to install Amazon's app store. Now that means you have to allow 3rd party apps so they can fully control your phone. Very insecure, but okay. Then I had to buy some 'Amazon coins" because any other payment method did not work, even though I customarily order books to my country from this account. Fine, I bought them and got the apps. But then I realized to my horror that Amazon injects code into them that only allows you to use the aps when you are currently logged into your Amazon account on the phone! Not only that, they also automatically activated the 1-click buy function!
Not only do these apps take an eternity to start now (boy, this log-in check must be complicated), if somebody grabs my phone he can now order anything with one click and has full access to my Amazon account! How crazy is that?
On the plus side, their customer service is top quality. The only thing they aren't allowed to tell you, but probably wish they could, is that you should not use Amazon's "app shop" under any circumstances ....
--end of rant--