Separate User from App Database - iphone

Question

My app just got rejected by Apple with the following reason:
2.23
We found that your app does not follow the iOS Data Storage
Guidelines, which is required per the App Store Review Guidelines.
In particular, we found that on launch and/or content download, your
app stores 10.3 MB. To check how much data your app is storing:
Install and launch your app
Go to Settings > iCloud > Storage & Backup > Manage Storage
If necessary, tap "Show all apps"
Check your app's storage
The iOS Data Storage Guidelines indicate that only content that the
user creates using your app, e.g., documents, new files, edits, etc.,
may be stored in the /Documents directory - and backed up by iCloud.
What I do is, I deliver the database in the resource folder with about 10 MB and copy that database to the library path on initial startup (see code below). When looking at my app settings after the startup within the device settings, it actually says, that the documents & data folder contain this 10 MB of data. The app does not need that database anymore when it is once installed, so I just tried to remove the DB from the resource folder, when the copy is done by using the removeItemAtPath. But there seems to be a permission issue with that.
Here the code I am using to populate the database at initial startup:
// Copy the database from the app resource, if it is not already existing in the library path
- (void) copyDatabaseIfNeeded {
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory , NSUserDomainMask, YES);
NSString *documentsDir = [paths objectAtIndex:0];
NSString *dbPath = [documentsDir stringByAppendingPathComponent:#"abiliator.sqlite3"];
BOOL success = [fileManager fileExistsAtPath:dbPath];
if(!success) {
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:#"abiliator.sqlite3"];
success = [fileManager copyItemAtPath:defaultDBPath toPath:dbPath error:&error];
if (!success) {
NSLog(#"Failed to create writable database file with message '%#'.", error);
}
else {
success = [fileManager removeItemAtPath:defaultDBPath error:&error];
if (!success) {
NSLog(#"Failed to remove the source database file with message '%#'.", error);
}
}
}
}
After researching for hours about that issue, I am actually pretty sure, that I am not doing ANYTHING wrong at all. The Library path is the location to store updateable files according to Apple documentation. Especially if the data is wanted to be backed up and hidden / not exposed to the user. Both is the case for my app, I want the data to be backed up and I don't want the user to see my database. So Library seems perfectly right. Only thing I could think of is the size of the database in the resource directory. I could reduce that by zipping it. But what are the limits? Neither the reviewers nor the documentation could tell me anything specific on that.
So what is actually wrong? And if the resource directory is not the right place to store my source database for initial setup, what other directory could I use in my project?
thanks a lot for any hint.
René

Answer 1

Got a reply from Apple mentioning that I am supposed to store the user data in a different database than the data I am delivering. Though I am not very keen on that, as it increases the code complexity unneccessary and the user data in my app can get larger than the one I deliver anyway, I would like to make sure, that I get the correct solution approach for that now.
What I intend to implement is 2 directories: /Library/UserDB and /Library/AppDB. The AppDB would contain the delivered DB and the UserDB would contain the user data only and I would flag the AppDB Dir as non-backup. Guess that would make Apple happy and get my app approved for that matter, am I right? Would appreciate any opinion about that approach before I start implementing.