How is Firestore billed?

When you use Cloud Firestore, you are charged for the following: The number of documents you read, write, and delete. The amount of storage that your database uses, including overhead for metadata and indexes. The amount of network bandwidth that you use.

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Why is Firebase asynchronous?

Firebase APIs are sensitive to the performance of your app’s main thread . This means that any Firebase API that needs to deal with data on disk or network is implemented in an asynchronous style. The functions will return immediately , so you can call them on the main thread without worrying about performance.

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