Я думаю, это то, что вы ищете:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES);
NSString *libraryPath = [paths objectAtIndex:0];
NSString *bundlePath = [libraryPath stringByAppendingPathComponent:[[NSBundle mainBundle] bundleIdentifier]];
if(![[NSFileManager defaultManager] fileExistsAtPath:bundlePath]) {
[[NSFileManager defaultManager] createDirectoryAtPath:bundlePath withIntermediateDirectories:YES attributes:nil error:NULL];
}