As somebody building my first react-native app at the moment, and planning to submit to the app store this week - thank you! 2 questions: 1. If you don't ask

As somebody building my first react-native app at the moment, and planning to submit to the app store this week - thank you! 2 questions: 1. If you don't ask the user to update immediately after it is downloaded, when will the update apply? The next time the app is opened? 2. Is it possible to handle events around the update process from from Javascript? (For example an `onBeforeUpdate` or `onAfterUpdate` event.)