I am developing an application that on the user's first login must download a lot of data from my server and store it in a local database in my iOS app.

In my server I am using MySQL. And I need to download 70MB... to my iOS app to use this data locally, having or not connection.

What's the best way to download this data? XML zipped? Export to a SQLite file, zip this file, and download?

Can you recommend any approach?