Steps to reproduce:

1. Open the attached project
2. Build the project for iOS
3. Run the project on a device that has iCloud set up
4. Wait a few minutes for all the asset bundles to finish downloading
5. When done, go to Settings/iCloud/Storage & Backup/Manage Storage and click on the current device
6. Notice that the application is taking up to 1GB of backup space

Workaround: Update the UnityUpdateNoBackupFlag function in Filesystem.mm file in Xcode project with this:

extern "C" int UnityUpdateNoBackupFlag(const char* path, int setFlag)
{
NSURL* URL= [NSURL fileURLWithPath: [NSString stringWithUTF8String: path]];
if(![[NSFileManager defaultManager] fileExistsAtPath: [URL path]])
return false;

NSError *error = nil;
BOOL success = [URL setResourceValue: [NSNumber numberWithBool: YES]
forKey: NSURLIsExcludedFromBackupKey error: &error];
if(!success){
NSLog(@"Error excluding %@ from backup %@", [URL lastPathComponent], error);
}
return success;
}