In a head-to-head fight between Amazon and Google, the former had to de-list( or banned?!) an app from Google Playstore.
Actually in September’14 , Amazon updated their app store and they enabled users access to their app store from within the app, this was technically legal from Google’s Android Developer Agreement, which said:
4.5 Non-Compete. You may not use the Market to distribute or make available any Product whose primary purpose is to facilitate the distribution of software applications and games for use on Android devices outside of the Market.
So, Google did not waste time and on 25th Sep’14, they came up with a hammer:
4.5 Alternative Stores. You may not use the Store to distribute or make available any Product which has a purpose that facilitates the distribution of software applications and games for use on Android devices outside of the Store.
Google changes DDA every now and then if it finds some loopholes are there which are working against it’s interest. Funny though, this time it has changed its policy to prevent alternative stores to be in Google Play itself!
Amazon has a big online market and has enough capability to cut a slice from Google play if it is given free pass in the Google store. Google does not want to loose its dominance over Android and it will try every measures to protect it.