Install iOS 12.1.2 for These Other Changes
iOS 12.1.2 doesn't come with any new features but if you skipped iOS 12.1.1 or iOS 12.1, you'll get some smaller features baked into your version of iOS 12.1.2.
Features from iOS 12.1.1 included a new one tap gesture to flip between the rear and front-facing camera during a FaceTime call, Live Photo capture during one-to-one FaceTime calls, the option to hide the sidebar in News on iPad in landscape orientation, Real-time text (RTT) when using Wi-Fi calling on iPad and iPod touch, and stability improvements for dictation and VoiceOver.
iOS 12.1.1 also brought some improvements to the HomePod. HomePod now supports Mainland China and Hong Kong and the HomePod LEDs will now illuminate during Group FaceTime calls.
If you skipped iOS 12.1, you'll get some additional features with your version of iOS 12.1.2.
iOS 12.1 added a performance management feature to prevent newer iPhone models from unexpectedly shutting down.
This includes the option to disable this feature if an unexpected shutdown occurs on the iPhone X, iPhone 8 or iPhone 8 Plus.
It's a controversial change, but Apple says "performance management may be less noticeable due to their more advanced hardware and software design."
The iOS 12.1 update also added the ability for Battery Health to inform you that it is unable to verify if a genuine Apple battery is in iPhone XS, iPhone XS Max, and iPhone XR and improved reliability of VoiceOver in Camera, Siri, and Safari.
iOS 12.1 users also discovered some additional tweaks including new padlock unlock animations on the lock screen, a new sound when pressing the camera and flashlight icon on the lock screen, a new Color under Face Gallery in the Watch app, and a redesigned Heart app icon in the Watch app.