Die wichtigsten Neuerungen in iOS4 im Überblick (englisch)

• Multitasking support for third-party apps
• Multitasking user interface to quickly move between apps
• Support for audio apps to play in the background
• VoIP apps can receive and maintain calls in the background or when device is asleep
• Apps can monitor location and take action while running in the background
• Alerts and messages can be pushed to apps using push and local notifications
• Apps can complete tasks in the background
• Folders to better organize and access apps
• Home screen Wallpaper
• Mail improvements
• Unified inbox to view emails from all accounts in one place
• Fast inbox switching to quickly switch between different email accounts
• Threaded messages to view multiple emails from the same conversation
• Attachments can be opened with compatible third- party apps
• Search results can now be filed or deleted
• Option to select size of photo attachments
• Messages in the Outbox can be edited or deleted
• Support for iBooks and iBookstore (available from the App Store)
• Photo and Camera improvements
• 5x digital zoom when taking a photo
• Tap to focus during video recording
• Ability to sync Faces from iPhoto
• Geo-tagged photos appear on a map in Photos
• Ability to create and edit playlists on device
• Calendar invitations can be sent and accepted wirelessly with supported CalDAV servers
• Support for MobileMe calendar sharing
• Suggestions and recent searches appear during a web search
• Searchable SMS/MMS messages
• Spotlight search can be continued on web and Wikipedia
• Enhanced location privacy
• New Location Services icon in the status bar
• Indication of which apps have requested your location in the last 24 hours
• Location Services can be toggled on or off for individual apps
• Automatic spellcheck
• Support for Bluetooth keyboards
• iPod out to navigate music, podcasts and audiobooks through an iPod interface with compatible cars
• Support for iTunes gifting of apps
• Wireless notes syncing with IMAP-based mail accounts
• Persistent WiFi connection to receive push notifications
• New setting for turning on/off cellular data only
• Option to display the character count while composing new SMS/MMS
• Visual Voicemail messages can be kept locally even if they have been deleted from the server
• Control to lock portrait orientation
• Audio playback controls for iPod and third-party audio apps
• New languages, dictionaries and keyboards
• Accessibility enhancements
• Bluetooth improvements
• Better data protection using the device passcode as an encryption key
• (Requires full restore)
• Support for third-party Mobile Device Management solutions
• Enables wireless distribution of enterprise applications
• Exchange Server 2010 compatibility
• Support for multiple Exchange ActiveSync accounts
• Support for Juniper Junos Pulse and Cisco AnyConnect SSL VPN apps (available from the App Store)
• More than 1,500 new developer APIs