Lightweight iOS 9 features smarter search, improved multitasking, and less battery drain. Apple's OS update for iPhone, iPad, and iPod Touch also reinvigorates the Notes and Maps apps with exciting new features and adds the News app to improve your news-reading experience.
Lightweight: iOS 9 requires only 1.3GB of free space, less than one third of that required by iOS 8. The extra space will be particularly useful for shutterbugs, app enthusiasts, and anyone with a 16GB iPhone.
News app: iOS 9 introduces the News app, a virtual newsstand containing many of your favorite newspapers, magazines, websites, and blogs. Explore publications by brand, category, or topic, and enjoy elegantly laid-out articles optimized for your device.
Notes, Maps, and Passbook improvements: The Notes app is now more dynamic, giving you the ability to add maps, links, and photos. Scribble in various stroke styles and colors, and search previously uploaded photos and maps in the new Attachments Browser. Maps adds public transportation directions under the Transit tab, and the new Nearby feature tells you where to pick up a cup of coffee or grab a new shirt en route to your destination. Passbook, Apple's payment app, is now called Wallet and works with many popular department store and rewards cards.
Keyboard: Helpful new keyboard shortcuts appear when you're composing an email or document. For example, select and toggle the BIU button to bold, italicize, and underline text; or tap the copy and paste buttons. Press the shift button to shift keyboard characters to uppercase or lowercase.
Improved search: Now Siri, your personal search assistant, is smarter, more predictive, and more responsive, based on your usage. In iOS 9, Siri also powers the Spotlight search bar, so you'll get relevant apps, contacts, businesses, and news on the search page, based on your location or time of day. Ready for some tunes? Just plug in your headset and the music app will show up.
Chronological notifications: Notifications inside the pull-down Notification Center are now ordered by day and time, making them easier to find and clear.
Increased battery life: Manually enabling Low Power Mode under Settings, then Battery, saves battery by disabling mail fetch, background app refresh, automatic downloads, and certain visual effects.
Enhanced security: Your device is now more secure, thanks to iOS 9's addition of six-digit passcodes and two-factor authentication.
iPad updates: The iPad's keyboard can now double as a trackpad. For those with the latest iPads, there are new multitasking features: Slide Over, Split View, and Picture in Picture to enable you to easily work in multiple apps at once.
Move to iOS: Apple's new Move to iOS app, available in the Google Play store, helps you transfer contacts, photos, calendars, and more from Android to iOS 9. The app will also suggest apps to download based on your previous app library.
Not for every device: To install iOS 9, you must have at minimum an iPhone 4S, iPad 2, iPad mini, iPad Air, or fifth-generation iPod Touch. To take advantage of all the new multitasking features for iPad, you'll need an iPad Air 2 or the upcoming iPad Mini 4 or iPad Pro.
iOS 9 brings with it the new News app, a better Notes and Maps experience, improved search, and more efficient battery use. Apple even incentivizes Android users to switch with the new Move to iOS app.
Before installing iOS 9, check out CNET's tips on how to upgrade your devices.