In this Firebase course on Android, learn what Cloud Firestore is and how it can be used to provide a NoSQL cloud-hosted Database for your app. Learn how to read and write data to Firestore from an Android application, listen to display changes in Firestore data in realtime, and use Firebase security rules to secure your Firestore data. Also, write some complex Firestore queries to sort and filter through displayed data. By Oday Maleh.