Hopefully by now you\u2019ve heeded the repeated warnings from your friends and loved ones (and friendly, beloved internet writers) to use two-factor authentication to secure your digital accounts. That\u2019s where access to Facebook or Twitter or your online bank\u2014anything that supports it, really\u2014requires not just a password but also a special code. Not all two-factor is created equal, however. For better protection, you\u2019re going to want an authenticator app.