I just bought this box, so far pretty happy with it, but speaking about Amazon prime video app, its functionality seems limited or, simply put, awkward.
When I asked Google Assistant to install the app, it jumped and did it without any issues, but if I try to look at the app inside the Google play market, shows me it's not supported.
Whaaaat?.....
My understanding is Amazon seems to be unaware about activating the device at the Play Store console, thus we can't find it at the Play Store because official support was announced when Android 9 beta arrive and the app came included inside the firmware update. I had a similar issue with another app and I had to contact the developer to include the device I was using at that moment.
Try installing the app from an apk,but make sure it's the android tv version e.g. https://prime-video-android-tv.en.aptoide.com/app
Have a look at this post
https://t.me/miboxsindia/206347
It's clear that mi box s is not yet supported, xiaomi has just side loaded or preloaded an old version of prime apk which can't be updated via play store.
Needs to be updated via some third party store.
In my opinion xiaomi has to pay for certification to Amazon to get the app whitelisted so that it can be downloaded from the app store.
Xiaomi will not pay for certification to save money.
I might be wrong on this.
But whenever we try to ask for clarifications from xiaomi support they never give a clear answer.
Users must ask xiaomi for clarifications....