Get the latest version
Both apps update themselves. Here's how to check, and when not to.
Chrome + iPad
Chrome
Chrome updates Backstage by itself, usually within a day of a new version. Closing and reopening Chrome helps it along.
iPad and iPhone
Open the App Store, tap your picture, and update Backstage from the list. Your version is in Backstage under Settings › Help & account › This build.
Never update in the middle of a show. An update swaps the app out while it's running. Wait until you've saved your manifest.