iOS 12.1.4 is the latest minor update for any compatible device, including iPhone 5S or newer, iPad Mini 2 or newer and iPod Touch 6th generation or newer. You should get automatic notification about this update. Alternatively, you should go to Settings> General> Software Update, to download the software manually. Weighing in at about 500MB, it’s quite large for a supposedly minor update.
Be aware that iOS 12.1.4 update will not support jailbroken iOS devices. It’s quite common for users with jailbroken iPhone to get quite far behind latest iOS releases. Unfortunately, there are reports that iOS 12.1.4 fails to fix some existing issues and it actually introduces some new ones. Problems associated with iOS 12.1.4 include photo glitches, broken voice memos and performance problem with TouchID and AirPods playback.
Ongoing WiFi problem isn’t fixed yet and some users still get disabled carrier data, two issues that hit users globally. Although it still doesn’t fix all problems, iOS 12.1.4 is still an essential upgrade. Apple confirmed that iOS 12.1.4 is intended to fix FaceTime bug, which allow callers to access audio and video data without detection.
Also, Apple said that the Live Photos bug has been resolved, along with a couple of memory exploit issues, discovered by a Google security engineer. This security issues have been exploited by hackers to attack iPhones. Although, it’s clear that iOS 12.1.4 isn’t completely secure, you still need to download it, because the FaceTime flaw is a very serious security hole.
The bug is found to affect devices with earlier iterations of iOS 12.1. Devices with much older iOS versions are not affected by this vulnerability. Apple is also working on iOS 12.2 update. Other than various bug fixes, it also offer some new features, such AirQuality to Apple Maps, Home Controls for TVs, HomeKit TV Support and upgrades to Safari web browser. There also numerous tweaks for other apps. WiFi and cellular data issues affect usability seriously, so Apple needs to focus on these problems as well.