the data story is one of the most important scenarios we are looking to cover in NativeScript, so we will offer you with a full stack implementation for it.
We are working on a data sync component which will be available for iOS, Android and Windows. you can read more about it here - http://www.telerik.com/datasync-beta
You will get access to the SQLite and you will also be able to work in offline mode and sync changes with a cloud server when internet connection is present.
This should be available as a preview for NativeScript sometime in March.
Please let me know if you have more questions about it.
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