Nearly five months after Apple rolled out iOS 4 in tandem with the iPhone 4 launch, it has released the latest update for the software that powers its touch-screen lineup: iOS 4.2.1 (along with version 4.1 for the latest-generation Apple TV). The free update is a major milestone for Apple: It finally unifies the iPhone, iPad and iPod Touch so that all are running the same operating system with the same major feature set. The update also adds several key new features.
The iPad stands to gain the most improvements -- it's been running the older iOS 3.2.2, which lacks features already available on the iPhone -- but all of Apple's iOS devices that can run the updated software will benefit. However, not all models will be able to use every new feature. iOS 4.2 is compatible with the iPhone 3G, 3GS and 4, as well as the iPad and every generation of the iPod Touch except the first one. Certain features, such as AirPrint, will work only on newer devices. (More about this in a moment.)
Here's a look at the major changes and improvements iOS 4.2 delivers.
The iPad gets the most changes
The arrival of iOS 4.2 will be most significant for iPad users, who have been stuck using an older, more limited version of iOS. Numerous software tweaks and improvements result in a much more polished user experience for iPad owners and will likely spur even faster enterprise adoption.
Threaded e-mail messages, third-party multitasking, fast-app switching, drag-and-drop app organization via folders, the addition of Faces/Places tagging in Photos, and wireless app distribution are all overdue additions.
The iPad already supported major VPN protocols; iOS 4.2 adds support for SSL VPN, giving users another way to connect securely to the office. Business users will also appreciate the newly unified e-mail in-box in the Mail app; you no longer have to navigate back and forth between multiple in-boxes when checking e-mail. And IT staffers will like the additional built-in management capabilities that allow them to better secure iPads in the office.
There are a few changes specific to the iPad. Unlike the iPhone's and iPod Touch's smaller screens, the iPad's larger one allows for the addition of a brightness slider within the multitasking bar, alongside the volume and audio controls. (The multitasking bar is the strip of icons that appears when you double-click the Home button.) Another iPad-specific tweak is the ability to choose photo size settings when you display more information in Mail messages.
And the switch on the iPad's side that has been used to lock the screen rotation becomes a mute switch, like that of iPhone and iPod. The lock-screen option has now been relocated to the multitasking bar, next to the aforementioned audio and brightness controls.
The iPad isn't the only hardware getting welcome updates. Since the debut of iOS 4, iPhone 3G owners have complained that that operating system runs slowly on their phones -- an issue Apple vowed to fix. Although I haven't yet tested iOS 4.2 on the iPhone 3G, others have -- and the early word is that the iPhone 3G does, indeed, get performance improvements.
AirPlay: Streaming wirelessly
By far the most anticipated new feature in iOS 4.2 is AirPlay. AirPlay allows you to transmit photos, video or audio to another source, such as video to an Apple TV or music to a compatible sound system. The emphasis here is on transmit: You're not transferring the data to the other device, you're streaming it wirelessly.
Why is this useful? If you've ever wanted to show a group of friends content on your iPad or iPhone without making everyone crowd around the suddenly too-small screen, this is the solution. Now you can zap that video to your TV instead. Or if you're listening to music with headphones and want to continue the song on your home sound system, you can do that, too.
Not surprisingly, Apple's implementation of this feature is simple. When your iPad/iPhone/iPod Touch is connected to a wireless network with an AirPlay-compatible device (such as an Apple TV or Denon sound system, an additional icon appears near the content controls. Tapping the icon allows you to choose whether to keep playing the content on the device in your hand or to play it on another device listed in a pop-up menu. There's no setup and nothing to configure. It just works, and it works fairly well, even when streaming audio content in the background. One note: AirPlay only plays video that works in iTunes.
I did run into glitches in some background audio streams while the iPhone was in the middle of heavy photo processing, but I openly admit I was trying to stress test the new OS.
Any app that supports video or audio can transmit to an AirPlay-compatible device, which means that a non-Apple app like Pandora can be used to stream music to other devices on your wireless network. Even better, high-definition (720p) and 5.1 surround sound are supported, though the quality obviously depends on the source. Most content can even be streamed in the background, so you can transmit that Tom & Jerry episode to an Apple TV for your kids to watch while you surf on your iPad. There's a feeling of living in the future now that comes with being able to take content and fling it, wirelessly, to a TV or stereo.
Apple has at last brought direct printing to the iPhone, iPad and iPod Touch. Until now, printing anything from these devices has required specific apps, such as Epson's iPrint or HP's iPrint Photo. But there's something of a catch: Currently, the number of printers supported by iOS's new AirPrint feature is extremely limited. Obviously, Apple couldn't pack every print driver for every printer into iOS; the compromise, in this case, is that only a handful of printers -- five from HP, one from Epson -- actually support the standard that Apple uses in iOS 4.2.
For the moment, AirPrint works with the following printers:
* HP Photosmart Premium Fax e-All-in-One Printer - C410
* HP Photosmart Premium e-All-in-One Printer series - C310
* HP Photosmart Plus e-All-in-One Printer series - B210
* HP Envy 100 e-All-in-One Printer Series - D410
* HP Photosmart eStation Printer series - C510
* And the Epson Artisan 835 all-in-one.
If you use one of those printers, you're in luck. If not, then for the time being, you're better off using the apps from print manufacturers found in the App Store. (A feature once touted for iOS 4.2 -- being able to print to a printer connected to a Mac or PC -- was dropped before the update was released.) While not everyone will be able to use AirPrint right away to print directly to a printer, it's a forward-looking feature that will grow in importance as more printer manufacturers catch on and adopt Apple's standard. Third parties will also need to update their apps to use the new feature.
AirPrint, when available, is located under the Option arrow button found in iOS apps on the iPad such as Mail, Photos and Safari. After tapping the button, you can choose the destination printer, number of copies and advanced features such as duplex printing for single- or double-sided output. Note: Print Center -- the print queue manager -- is accessible only through the multitasking bar, and it's available only when printing is in progress.
In addition to the limited number of printers supported, there's another catch: AirPrint works only on iOS devices that support multitasking. This includes the iPad, the iPhone 4 and 3GS, and the third- and fourth-generation iPod Touch.
AirPrint offers the promise of easy printing over wireless networks, something I expect to be popular in the workplace environment. While only a handful of printers support the standard out of the box, it's a start.
Apple has made enormous strides with iOS in the past few years, and iOS 4.2 delivers some features more typical to full-featured computer operating systems. In addition to those already mentioned, iOS 4.2 offers new MIDI support that allows musicians to connect keyboards and synthesizers -- through the dock connection or wirelessly -- to iOS devices. This will be popular with musicians who use Apple's iOS devices, though it's not something I've tried.
Clearly, the line between mobile devices and computers is becoming increasingly blurry. But there are still some features that Apple has yet to implement that would build on iOS 4.2 and make the iPad, iPhone and iPod Touch even more useful. In particular, I'd like to see custom alert sounds, quick-reply from message notifications, the ability to delete phone log entries individually, the ability to use the iPhone and iPad as external hard drives, and a unified notifications area. I'm hoping those features get some attention with the next big release of iOS.
Even so, iOS 4.2 is a welcome update that builds upon what Apple started with the original iPhone. Each iteration rolls out useful new features and routine improvements. During my testing, I didn't encounter any apps that crashed or refused to launch. That kind of stability -- and the awesome AirPlay technology -- inspires confidence in recommending the free upgrade.
Michael deAgonia, a frequent contributor to Computerworld, is an award-winning writer, computer consultant and technologist who has been working on computers since 1993. You can find him on Twitter.