Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
This sounds like this is an app Amazon has released for Android devices running the Amazon Appstore app. There is no mention of availability on Roku.
As for regular prime Video, there is a Roku channel app for this you can install from the Streaming channels option on your Roku TV home page. This requires a paid subscription. This can be obtained as part of an Amazon Prime subscription, or I think I've read you can subscribe to Prime Video only. When the app is installed and loaded click on the "gear" icon in the upper right and Sign In into your Prime account.
Doug Roku Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Roku Streaming Stick 3600
Roku Community Streaming Expert I am not a Roku employee, just a user like you.
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