Apple offers optional two-factor authentication to lock down iTunes, iCloud and Apple Store accounts. Security experts commended Apple, even though the company was slow pulling the trigger. The new feature is designed to block unauthorized changes to iCloud or iTunes accounts, and keep hackers who steal Apple IDs from purchasing digital content or hardware using the credit cards stored in customers’ iTunes accounts. Facebook, Google and Microsoft also offer two-step authentication to help customers secure their Apple IDs against hacking. Apple, while not at the forefront of the technology, “They seem to be slow to implement all kinds of things that seem so obvious to everyone else””]