UPDATE (Oct 12, 2011 10:00am PST): It’s Available now!

Step 1. Download the New iTunes 10.5.

Step 2. Back up your phone.

Step 3. Update to iOS5

A remarkable revamp of the iOS system, the Apple iOS 5 will bring a number of key features to Apple’s mobile device users with twitter integration together with the improvements on mail functionality and bringing new tools, such as rule of third grid lines, to devices’ cameras.

Apple iOS 5 update will be available for iPhone 3GS, iPhone 4, iPhone 4S, iPad, iPad 2 and iPod Touch

Here are the list of the improved features

• Apple iOS 5: iMessage

A new messaging service that lets you easily send text messages, photos and videos between all iOS devices. Built right into the Messages app, iMessage allows you to send text messages, photos, videos or contact information to a person or a group on other iOS 5 devices over Wi-Fi or 3G. iMessage also features delivery and read receipts, typing indication and secure end-to-end encryption.

• Apple iOS 5: Notification Centre

A way to easily view and manage notifications in one place without interruption. Notifications appear briefly at the top of the screen without interrupting what you’re doing. With one swipe you can see all your notifications, and a simple tap will take you right to its app for more detail. Notifications also appear on the lock screen, with the ability to be taken to the notifying app with just one swipe.

• Apple iOS 5: Camera

Improving things on the snapping front, iOS 5 notably adds the ability to use grid lines for rule of thirds composition, use a two-finger pinch gesture to zoom in and out, single-tap focus. Users will also be able to download photos to other iOS devices using Photo Stream via iCloud. Crucially you’ll also be able to get to the camera from the lock screen.

• Apple iOS 5: Reminders

The to-do list feature with support for Outlook and iCloud, iOS 5 will now help to organize your life making sure you are fully stocked up in the freezer with location based integration letting you know about your shopping list when you pull into the supermarket. When you make a change to your to-do list your iPad, iPod Touch or iPhone will be updated automatically.

• Apple iOS 5: Mail

A whole host of features will improve dealing with your email correspondence which include dragging email addresses between fields, flagging important messages, notifications when you’ve forgotten to add a subject line in an email, Hotmail integration and rich text editing support.

So, will you be updating your device? Hit the comment box and let me know your views.