The final big change to the iPhone 4S's hardware is its rear camera, which has been bumped from 5 megapixels to 8 and includes support for 1080p video capture, better optics in low-light situations, and electronic enhancements for image stabilization when shooting video. It's darn close to a pocket digital camera in quality, though I wish it had image stabilization when taking still photos.
Where the iPhone 4S feels behind is its screen size. The 3.5-inch screen is cramped, especially compared to the 4.3-inch screens that are becoming widely available in competing mobile platforms. A larger screen really should be part of the next-generation iPhone.
Except for the Siri service, the rest of what the iPhone 4S offers are the stock capabilities from iOS 5, which are also available to the iPhone 4 and, to a lesser extent, the iPhone 3G S.
Email, calendars, and contactsiOS 5 covers all the major bases for business communications: It can connect to multiple Exchange, IMAP, POP, and Gmail accounts; make and synchronize appointments; and manage contacts. It tries to autodetect your mail server settings wherever possible and does a good job of handling nonvanilla settings. There's a client app for Lotus Notes, and you can access GroupWise if you install its Exchange-compatible server add-on.
Email. I'm not a big fan of iOS's UI for mail accounts, which iOS 5 leaves unchanged. There's a unified inbox for all your email accounts, then a separate list of your accounts so that you can go to their traditional folder hierarchy (for Exchange and IMAP accounts). I don't know why Apple had to break these into separate lists; for someone like me with four separate email accounts, the result is extra scrolling to switch accounts based on the mode I want to see. Android 4 "Ice Cream Sandwich" handles multiple accounts with a nicer, easier arrangement, though it doesn't preserve folder hierarchies in IMAP accounts. But iOS does let you designate which folders are automatically synced as part of the mail settings; competing mobile operating systems do not.
iOS 5 brings another welcome capability to email not available in competing mobile operating systems: the option to apply rich text formatting, including boldface, italics, underlining, and indentation. I only wish I could apply the character formatting while typing, such as through keyboard shortcuts or formatting buttons, rather than have to select the text first and then apply the formatting via the contextual menu.
iOS's native Quick Look viewer handles a nice range of formats (Microsoft Office, Apple iWork, PDF, text-only, and Web graphics formats), and it opens attachments with one tap, even downloading them if needed at the same time. But iOS 5 -- still! -- doesn't open zip files without the aid of a third-party app such as the Swiss Army Knife file utility GoodReader ($5) or a dedicated unzipper such as ZipBox Pro ($2) and Unzip ($1).
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