Apple iOS 5.0 - iPhone operating system; download with iTunes.. (Updater): 
Apple iOS can be downloaded from iTunes by connecting your iPhone and clicking the Update button.
Version 5.0:
Notifications
- Swipe from the top of any screen to view notifications in one place with Notification Center
- New notifications appear briefly at the top of the screen
- View notifications from lock screen
- Slide the notification app icon to the right on the lock screen to go directly to the app
iMessage
- Send and receive unlimited text, photo, and video messages with other iOS 5 users
- Track messages with delivery and read receipts
- Group messaging and secure encryption
- Works over cellular network and Wi-Fi
Newsstand
- Automatically organizes magazine and newspaper subscriptions on Home Screen
- Displays the cover of the latest issue
- Background downloads of new issues
Reminders for managing to do lists
- Syncs with iCloud, iCal and Outlook
- Location-based reminders when you leave or arrive at a location for iPhone 4S and iPhone 4
Built-in support for Twitter
- Sign-in once in Settings and tweet directly from Camera, Photos, Maps, Safari and YouTube
- Add location to any tweet
- View twitter profile pictures and usernames in Contacts
Camera improvements for devices with cameras
- Double click the home button when device is asleep to bring up a camera shortcut on iPhone 4S, iPhone 4, iPhone 3GS and iPod touch (4th generation)
- Volume Up button to take a picture
- Optional grid lines to line up shots
- Pinch to zoom in the preview screen
- Swipe to camera roll from preview screen
- Tap and hold to lock focus anxd exposure, iPad 2 and iPod touch (4th generation) only support exposure lock
Photo improvements for devices with cameras
- Crop and rotate
- Red eye removal
- One tap enhance
- Organize photos into albums
Mail improvements
- Format text using bold, italic, or underlined fonts
- Indentation control
- Drag to rearrange names in address fields
- Flag messages
- Mass mark messages as flagged, read or unread
- Customize mail alert sounds
- S/MIME
Calendar improvements
- Year view on iPad and new Week view for iPhone and iPod touch
- Tap to create an event
- View and add event attachments
Game Center improvements
- Use personal photos for your Game Center account
- Compare your overall achievement scores with your friends
- Find new Game Center friends with friend recommendations and friends of friends
- Discover new games with custom game recommendations
AirPlay Mirroring for iPad 2 and iPhone 4S
Multitasking Gestures for iPad
- Use four or five fingers to pinch to the Home Screen
- Swipe up to reveal the multitasking bar
- Swipe left or right to switch between apps
On-device setup, activation and configuration with Setup Assistant
Software updates available over the air without tethering
iCloud support
- iTunes in the Cloud
- Photo Stream
- Documents in the Cloud
- Apps and Books automatic download and purchase history
- Backup
- Contacts, Calendar, and Mail
- Find My iPhone
Redesigned Music app for iPad
Hourly weather forecast
Real-time stock quotes
Wireless sync to iTunes
Keyboard improvements
- Split keyboard for iPad
- Improved autocorrection accuracy
- Improved Chinese and Japanese input
- New Emoji keyboard
- Personal dictionary for autocorrection
- Optionally create keyboard short cuts for frequently used words
Accessibility improvements
- Option to light LED flash on incoming calls and alerts for iPhone 4S and iPhone 4
- Custom vibration patterns for incoming calls on iPhone
- New interface for using iOS with mobility-impairment input devices
- Option to speak a selection of text
- Custom element labeling for VoiceOver
Exchange ActiveSync improvements
- Wirelessly sync tasks
- Mark messages as flagged, read or unread
- Improved offline support
- Save a new contact from a GAL service
More than 1,500 new developer APIs
Bug fixes
Supports:
- iPhone 3GS / 4 / 4S
- iPad / iPad 2
- iPod Touch 3rd Gen / 4th Gen
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