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See also, best iPhone 5S apps to download first
Moreover, anyone buying a new iPhone can now download Apple's iWork and iLife apps for free. These include Pages for word processing, Keynote for presentations, Numbers for spreadsheets, iPhoto for photo editing and iMovie for video editing. All, with the arguable exception of the rather confusing iPhoto app, are solid apps and the fact they're free makes them all the more attractive. They integrate seamlessly with iCloud, too, so documents created on your iPhone are synched.
iOS 7 sees numerous other improvements, too. Siri has new features that makes it easier to use and more useful and many of the core apps are improved, but we suggest you read our comprehensive iOS 7 review for all the details as there's plenty more about the iPhone 5S we need to cover.