docs: core docs

Author: Krzysztof Borowy

packages/core/README.md

@@ -0,0 +1,59 @@
+# Async Storage Core
+
+Main Async Storage component. 
+
+## Installation
+
+```bash
+$ yarn install @react-native-community/async-storage
+```
+
+## Usage
+
+Use `AsyncStorageFactory` to create your Async Storage instance 
+
+
+```typescript
+
+// storage.js
+
+import ASFactory from '@react-native-community/async-storage'
+
+// use any available Storage Backend
+const storageBackend = new StorageBackend();
+
+const mobileStorage = ASFactory.create(storageBackend);
+
+export default mobileStorage;
+```
+
+## Providing a storage model
+
+You can provide a `Model` type when creating Async Storage, to have a fully typed storage. 
+
+
+```typescript
+import ASFactory from '@react-native-community/async-storage'
+
+type StorageModel = {
+  user: {
+    name: string;
+    age: number;
+  };
+  preferences: {
+    darkModeEnabled: boolean;
+  };
+  subscribedChannels: Array<Channel>;
+  onboardingCompleted: boolean;
+};
+
+// use any available Storage Backend
+const storageBackend = new StorageBackend();
+
+const storage = ASFactory.create<StorageModel>(storageBackend);
+
+```
+  
+## License
+
+MIT.