San Francisco - Apple said it's pointing the way to a post-PC world with the planned fall launch of the iOS5, which integrates with the company's new iCloud service.

The content includes apps, pictures and videos as well as documents created in iWorks on Apple's mobile devices.

The free iCloud service, launching simultaneously with iOS5, will also automatically sync contacts, calendar updates and email updates among multiple devices via cellular and Wi-Fi. Via Wi-Fi, devices will also automatically back up their content once per day to the Cloud.

The service will also let users buy an app, song or e-book from the iTunes store and automatically push it from the Cloud to a total of 10 iOS devices. With the service, users can also manually upload all their ripped songs to the Cloud to synchronize them via Wi-Fi with all their iOS devices, or they can pay $29.99/year for an iTunes Match service that will scan the songs on a device, match them to iTunes's 18 million songs, and push higher-quality versions of the songs to multiple iOS5 devices.

Also to cut a mobile device's connections to the PC, iPhone purchasers won't have to connect their iPhone to a PC to activate it, and they'll be able to download iPhone software updates over the air. iOS users will also be able create calendars and mailboxes right from their mobile device.

In another major change, Apple is creating its own messaging service to let iOS5 users send encrypted text, picture and video messages via Wi-Fi or cellular to all other iOS5 users, even those using an iPad or iPod Touch.

Those are among the more than 200 changes that Apple announced for its iOS here at its worldwide developers conference, where CEO Steve Jobs stepped away from medical leave to announce the iCloud services.

Other iOS changes include wireless syncing via Wi-Fi from a mobile device to a PC; multitasking gestures that will, for example, let users flick between apps; and wireless AirPlay Mirroring, enabling an iPad 2 to wirelessly transmit what's on its screen to a TV via the Apple TV device.

For storing email, documents and backup, consumers get 5GB of storage for free. The 5GB excludes storage for music, apps and books purchased from Apple and for photos.

Users will be able to buy additional storage at a rate to be announced in the fall.

For synchronizing pictures, iCloud will store picture for 30 days, and each iOS device will automatically store the last 1,000 pictures uploaded to the Cloud. Macs and PCs will store all pictures permanently until manually deleted.

Other new features of iOS5 include:

--visual notification of email, calendar updates, SMS messages, and news and sports alerts at the top of the screen, similar to what the Android OS does, without interrupting use of an app;

-- a newsstand feature that groups all magazines and newspapers in a newsstand app, which downloads newspapers and magazines in the background;

-- Twitter integration with apps, enabling users to do such things as Tweet a picture from the photo app;

-- an Improved Safari web browser that lets users move a web story to the front and center of the screen and append multiple pages of the story into one long page;

-- a reminders app that not only sends reminders to do tasks but also emits GPS-based reminders, such as emitting an alert to call someone as you get neat the convention center or hotel;

-- ability to access the camera app from the lock screen to take pictures quickly; and

-- the ability to split the virtual QWERTY keyboard into two for thumb typing.

Also at the developer's conference, Apple unveiled the Lion version of its OS X for Macs, which is due in July and is priced at $29.99 for downloading to all authorized Macs owned by the purchaser.

The upgraded OS adds multitouch gestures on a touchpad, a Mission Control user interface that lets users get to any window via three-finger swipe, Launch Pad feature to launch apps quickly via pinching, an auto-save function to automatically save documents, and a resume feature to resume where you left off in an application after closing and then reopening the application.

 Other Lion enhancements include built-in Mac App Store, peer-to-peer Wi-Fi sharing of content, and built-in FaceTime.