Firebase cloud functions can be secured through various mechanisms supplied by Firebase with out-of-the-box features: 1. Functions can easily determine whether the user is being called by a user who has been authenticated by Firebase Auth 2. We can use Firebase App Check to ensure Functions can only be called

An essential part of maintaining user engagement with mobile applications is sending push notifications at the appropriate time.  Push notifications come in two flavors: * Local push notifications: notifications scheduled by the app itself, based on internal events.  For example, a simple timer app could schedule a push notification to alert