What is the latest iOS version on iPhone and what issues it addressed? 
 The latest iOS for Apple iPhone is iOS 16.4.
This has bought a lot of updates to the iPhone like:
- It introduced a new set of emojis
- latest security patch 
- It introduced a voice isolation feature for iPhone, now people can not listen to background noise when they are on call
- Now Cloud Shared Photo Library can also detect duplicate photos, this will save your storage
- Crash detection is been optimised for iPhone 14 series phones
- iCloud was unresponsive sometimes has been addressed
- Now you can add notifications for web apps on the home screen itself.
- Many more features are added