iOS 12 Security Series 1/5: Apple released its latest update to iOS, the OS on iPhone and iPad. We'll post a few security-related updates over the next few days. First: restrict what can be done from your lock screen in Settings > Touch ID & Passcode. The new feature as of iOS 12 is "USB accessories" which helps prevent hacking attacks, but you can also restrict the ability to use Siri or your Wallet etc., from your locked iPhone.