The new feature, introduced a few months back, is Battle.net SMS Protect. It's a free service, as long as your mobile phone service provider doesn't charge you to receive text messages, in which case text messages would be charged at the usual rate. SMS Protect cannot use any type of messaging other than text messaging, and doesn't require a smartphone to work -- all your phone needs is the ability to receive SMS text messages, making this a nice feature for those players who don't have smartphones.
There have been mixed reports on whether it works with prepaid mobile phones, but where it hasn't been working that's usually because carriers don't allow the receipt of SMS text messages.
SMS Protect is not designed to replace the authenticator, either the phone authenticator or the physical authenticator. Rather, it is an alert system, designed to warn you about suspicious activity on your account, and allow you to perform certain actions with your phone. Hit the break for more information!
Filed under: Account Security