No, you do not need to purchase or install any new components to enjoy the benefits of voice control through Amazon Alexa.
If you've already downloaded the Moen Smart Water App onto your smartphone, and provided automatic approval of updates, the App will push the update with Amazon Alexa automatically to your device.
If you haven't yet downloaded the Moen Smart Water App, see the question "How do I pair my Smart Shower with my Amazon devices?" above.
To ensure you have the latest version of the Moen Smart Water App, open the Apple App Store or Google Play Store and search for the Moen Smart Water App. Select "Update" if the App is currently operating as a previous version. Once you’ve updated the software, it will be ready to use with your Alexa-enabled devices.