iOS 11 Officially Released By Apple. What's new in iOS 11 & Features.

For Download Settings -> General -> Software Update -> Download and Install.

iOS 11 is performance optimised for 64-bit apps. 32-bit apps will need
to be updated by the app developer to work with this version of iOS.

Supported Devices :

iPhone

• iPhone 7 Plus
• iPhone 7
• iPhone 6s
• iPhone 6s Plus
• iPhone 6
• iPhone 6 Plus
• iPhone SE
• iPhone 5s

iPad

• 12.9-inch iPad Pro (first-generation)
• 12.9-inch iPad Pro (second-generation)
• 9.7-inch iPad Pro
• 10.5-inch iPad Pro
• iPad (fifth-generation)
• iPad Air 2
• iPad Air
• iPad mini 4
• iPad mini 3
• iPad mini 2

iPod touch

• iPod touch (6th generation)

iOS 11 brings hundreds of new features to iPhone and iPad including following :

App Store:

All-new App Store designed for discovering great apps and games every day.

New Games tab to find new games and see what’s most popular with top game charts.

New Today tab helps you discover new apps and games with stories, how-to guides and more.

 

Siri :

New Siri voice is more natural and expressive.

Translate English words and phrases into Chinese, French, German, Italian or Spanish (beta)

Siri suggestions based on your usage of Safari, News, Mail and Messages.

Works with banking apps for account transfer and balances.

Works with apps that display QR codes.

Hindi and Shanghainese dictation.

 

Camera :

Portrait mode now supports optical image stabilisation, HDR and True Tone flash.

Photos and videos will take up half the space with the new HEIF and HEVC image and video formats.

Redesigned set of nine filters optimised for natural skin tones.

Automatically identify and scan QR codes. 

Photos :

Loop, Bounce and Long Exposure Live Photo effects.

Mute, trim or choose a new key photo for Live Photos.

Memory Movies automatically adapt content for portrait and landscape orientation.

More than a dozen new memory types including pets, babies, weddings and sporting events.

People album is more accurate and stays up to date across devices with iCIoud Photo Library.

Animated GIF support.

Maps :

Indoor maps for major airports and shopping centres.

Lane guidance and speed limit information with Turn-by-turn directions.

One-handed zoom with double tap and swipe.

Interact with Flyover by moving your device.

Do Not Disturb While Driving :

Automatically silences notifications while driving and keeps iPhone.

Optional Message auto-reply to alert selected contacts that you're driving.

New features designed for iPad :

An all-new Dock provides quick access to your favourite and recently used apps and can even be shown on top of active apps.

    Dock resizes so you can add all your favourite apps
    Recently used and Continuity apps are available on the right

Enhanced Slide Over and Split View

    Apps can be easily started in Slide Over and Split View from the Dock
    Slide Over and background apps now run simultaneously
    Apps in Slide Over and Split View can now be placed on the left side of the screen.

Drag and drop

    Move text, images and files between apps on iPad
    MuIti-Touch to move multiple items at the same time
    Spring-loading to move content between apps

Markup

    Markup works across documents, PDFs, web pages, photos and more
    Instantly mark up anything in iOS - just place Apple Pencil on what you want to mark up.

Notes

    Instantly create a new note by tapping the Lock screen with Apple Pencil.
    Inline drawing available by simply placing Apple Pencil in the body of a note.
    Search handwritten text.
    Document scanner auto-corrects for skewing and uses image filters to remove shadows.

Files

    AII-new Files app to browse, search and organise files.
    Works with iCIoud Drive and third-party cloud file providers.
    Recents view for quick access to recently used files across all apps and cloud services.

QuickType :

Flick down on letter keys to enter numbers, symbols and punctuation marks on iPad.

One-handed keyboard support on iPhone.

New keyboards for Armenian, Azerbaijani, Belarusian, Georgian, Irish, Kannada, Malayalam, Maori, Odia, Swahili and Welsh.

Augmented Reality :

Augmented reality technologies that apps from the App Store can use to deliver content on top of real-world scenes for interactive gaming, immersive shopping experiences, industrial design and more.

sample projects on Augmented reality. 

Machine Learning :

Core machine learning technologies that apps from the App Store can use to deliver intelligent features with machine learning data processed on device for high performance and user privacy.

 sample project on Machine Learning.

Accessibility :

VoiceOver description support for images.

VoiceOver table and list support in PDFs.

Type to Siri support for basic search queries.

Spoken and braille caption support for videos.

Dynamic Type increases text and app UI to larger sizes.

Redesigned Invert Colours makes media content easier to view.


Some features may not be available in all countries or all areas.