You can now create IoT Analytics Channel and Data Stores in an Amazon S3 bucket in your AWS Account. This lets you easily integrate your IoT Analytics data with your existing data lake, manage the lifecycle of the data according to your S3 bucket policies, and use the data with a downstream application for further processing or presentation to end-users. Previously, your IoT Analytics data could only be used with an S3 bucket managed by the IoT Analytics service. With this feature, and the recently added support for sending IoT Analytics data set content to your Amazon S3 bucket, you now have the flexibility to use S3 buckets in your AWS account for both your IoT Analytics data and materialized views of it.
from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/05/aws-iot-analytics-now-supports-channel-and-data-stores-in-your-o/