Quite recently iOS 4 Software Update was released and creating waves. Now iPhone and iPod Touch users can upgrade to iOS 4 for Free. Earlier we discussed about the expected features of iPhone OS 4.
iOS 4 believed to contain lots of new features than the previous version and bug fixes.
Users are updating their OS and enjoying the new features. Below I mentioned some of the new features in iOS 4.

1# Multitasking
- Apps can complete tasks in the background.
- VoIP apps can maintain and receive calls.
- Audio apps can play in the background.
- Apps can monitor location while running in the background.
2# Photo and Camera Improvements
- 5x digital zoom.
- Easily ync Faces from iPhoto.
- Geo-tagged photos appear on a map in Photos.
- Ability to tap focus during video recording.
3# Mail Improvements
- Unified Inbox to view emails from all accounts.
- Fast Inbox switching to quickly switch between different Email accounts.
- Threaded messages to view multiple emails from the same conversation.
iOS 4 also believed to have support for Bluetooth keyboards and for third-party Mobile Device Management solutions.
So which feature you find the most interesting? Please share it in the comments.