you can use Realm or Sqlite if you want to manage complex data type.
Otherwise go with inbuilt react native asynstorage
you can use sync storage that is easier to use than async storage. this library is great that uses async storage to save data asynchronously and uses memory to load and save data instantly synchronously, so we save data async to memory and use in app sync, so this is great.
import SyncStorage from 'sync-storage';
SyncStorage.set('foo', 'bar');
const result = SyncStorage.get('foo');
console.log(result); // 'bar'