Question: The documentation says it should be used instead of LocalStorage, but it doesn't list anything regarding how large it is. If I recall, LocalStorage in web browsers is only about 10mb.

<https://facebook.github.io/react-native/docs/asyncstorage.html>

Answer: 
It writes to disk and is very large if there is free space. On iOS there are no artificial caps other than what the underlying operating system imposes: <https://stackoverflow.com/a/1897383/454967>.
### This is an old answer, the new method is mentioned in justin answer above..

---

As mentioned [here](https://stackoverflow.com/questions/38991073/react-native-async-storage-limit-on-android), to increase the **6mb** limit on Android.. try this:

in `MainApplication.java` add these lines in `onCreate` function

```
  public void onCreate() {
    // ...
    long size = 50L * 1024L * 1024L; // 50 MB
    com.facebook.react.modules.storage.ReactDatabaseSupplier.getInstance(getApplicationContext()).setMaximumSize(size);
  }

```