If you have already upgraded your iPhone to iOS 14.4, then you will no longer be able to switch back to iOS 14.3. Apple will no longer sign iOS 14.3. So, if you are facing any particular issue or bugs with any app on iOS 14.4 that was otherwise running smoothly on iOS 14.3 then the only option you have is to wait for Apple to release iOS 14.5 and wait for a solution. Apple has already released iOS 14.5 for beta users and only they can downgrade to iOS 14.4 but not to iOS 14.3 any longer.
Apple has added a range of features in the iOS 14.4 update. It has made it easier to use the HomePod mini with your iPhone. The iOS 14.4 update has a new feature for the HomePod mini that utilises the speaker’s U1 chip. When a U1 chip-based iPhone (iPhone 11 and above) is around the HomePod mini, a soft haptic touch rhythm starts which progressive gets faster the closer your iPhone comes to the HomePod mini. When close enough, an UI pops up to transfer songs to the HomePod mini. This makes handoff easier and better.
There are new features on the Apple Watch app like “Time to Walk” and “Add Newest Workouts to Watch”. The iOS 14.4 update includes the option to classify Bluetooth device type in Settings for correct identification of headphones for audio notifications. Your iPhone will also notify when the camera on your iPhone is unable to be verified as a new, genuine Apple camera in iPhone 12, iPhone 12 mini, iPhone 12 Pro and iPhone 12 Pro Max.
The iOS 14.4 update also enables user to scan small QR codes from the camera itself. Other fixes include image artefacts could appear in HDR photos taken with iPhone 12 Pro and Fitness widget may not display updated Activity data. It has also fixed issues like ‘the keyboard may not come up in the correct language in Messages’.