By default Mac Apps use XML as store type when saving in Core Data, even though it can use other formats – such as SQLite, which is the default on iOS. Here’s a way to quickly convert one into the other.
Note that this is designed as a one-off operation to create a new store file which can be used in another application. Once run, comment the code out and either change your store file, or take the store file and use it in another app.
Add this code to the AppDelegate.m file in the persistenStore method (just before the return statement):
// convert this thing to SQL
NSURL *sqlstore = [applicationFilesDirectory URLByAppendingPathComponent:@"NewStoreFile.sqldata"];
NSPersistentStore *xmlstore = [coordinator persistentStoreForURL:url];
[coordinator migratePersistentStore:xmlstore toURL:sqlstore options:nil withType:NSSQLiteStoreType error:nil];
For more information on how to do this in context, check out Simon Allardice’s superb course Core Data for iOS and OS X on Lynda.com.