Can I manage my app through the Developer Portal?.The publication details will also require you to add descriptions and metadata about your app. Consequently, you will need to manually create some image assets. When you start the app publishing process, Amazon Creator attempts to auto-create some of the required image assets for Appstore submission, but not all image assets are available from your YouTube channel or MRSS feed. After you create and preview your app, you're ready to publish your app on the Amazon Appstore.