Summary:
Once your app is live, you are free to change all metadata associated with the app. To update your app's metadata simply click on your app's title in the "My Apps" tab. Then choose the tab with the information you would like to edit. From there click the "Edit" button at the bottom of the page and make your changes. When you are finished make sure to Save your changes and then click the "Submit App" button to submit your changes for republishing.
