Where previous iOS versions allowed you to customize the device lock screen with custom wallpaper, iOS4 adds the ability to do so with the home screen(s) as well. There are a few limitations here, however. First, you must have a compatible device, meaning an iPhone 4, iPhone 3GS, or 3rd generation (late 2009) iPod touch; otherwise, you can only change the lock screen wallpaper as before. Second, if you maintain multiple home screens, as so many do, there's no way to place a different image under on each home screen, which would be nice. Instead, you can use the same wallpaper on the lock screen and all home screens, or one wallpaper on the home screen and one on all home screens. Your choice.
You can now use different wallpaper on the lock screen and, new to iOS 4, the home screen(s).
Apple already makes the best mobile browser out there so no major changes were needed in iOS 4. That said, there are some nice, small updates. Microsoft's Bing search engine has been added as an option alongside the pre-existing Google and Yahoo choices, suggesting that it's crossed some important usage plateau, or that Microsoft ponied up a certain amount of case. Either way, it's a nice addition.
More important, perhaps, each of the search engines now provides search suggestions via a nice list-based UI. So as you type a search query into the Safari search box, search suggestions will appear below, matching top searches to what you're typing.
The iPod app gets some nice upgrades in iOS 4, the best of which is the ability to create and edit playlists right on the device. This works as expected: There's a new Add Playlist choice in the Playlists and once you create and name a new playlist, you can easily add and manage the songs it contains. Additionally, because you can now edit existing playlists, you'll see options for Edit, Clear, and Delete and the top of each playlist screen. Simple and obvious.
Create and edit playlists on the device.
I won't spend too much time on this, because you need a Mac to take full advantage of it, but the Photos app is now compatible with the iPhoto Places and Events features. But there is limited Places functionality for one and all, because each photo you take is now geotagged for location, and Photos keeps a running tally of the places you've visited. So on a camera-equipped iOS device (iPhone 3GS and iPhone 4 only, currently), you can now browse by place as well as by album or camera roll. This will become more important and desirable as iPhone 4s proliferate, because these devices might actually have good enough cameras that many users could simply leave their dedicated cameras behind. I'm eager to see if this is the case.
Apple's Mail app for iOS has always offered what is, to me, the ultimate email triage solution, a way to delete and move emails that you don't need to deal with immediately, and do so with one hand. (Curiously, the iPad version of this app doesn't work as well because the necessary icons are so far apart you need to use two hands and careful balance the device in use.)
In iOS 4, Mail gets even better. The first major improvement is a unified inbox, so those who want to check multiple email accounts can now do so without moving in and out of each account. To see this view, configure the device with multiple email accounts, run Mail, and choose All Inboxes from the Mailboxes screen. (Alternatively, you can quickly access individual account inboxes or navigate through the entire folder structure for individual accounts.) I've loaded up my iPod with three email accounts and it works great.
iOS 4 supports multiple email accounts, including, for the first time, multiple Exchange accounts.
Mail also supports threaded messages now, so you consolidate lengthy email discussions into a single entry in the inbox. To see all the messages in a thread, just tap on the threaded message in the inbox.
Also, Mail sports a handy spellchecking feature--as do other apps, like Notes--providing a handy, Office-like red dotted underline under misspelled words. Tap the word and iOS displays a pop-up with potential fixes. Very nice.
While the iPhone 4 camera will bring a number of long-awaited and useful enhancements, like 5 megapixel resolution and LED flash, existing iPhone 3G and 3GS users won't need to upgrade to benefit from some advances. For example, tap to focus on video works on the 3GS, and both the 3G and 3GS get 5x digital zoom. It's not great on the existing devices--hey, those cameras are horrible, after all--but it's better than nothing. Much better.
Digital zoom works with still images only.
Zoomed photos, of course, don't always come out all that well. Note the heavy pixelation.
Apple iOS 4 offers a number of hardware support improvements, but the two biggest, in my opinion, are support for Bluetooth keyboards and an improvement to Wi-Fi networking.
For the former, you can now pair a Bluetooth keyboard with iOS 4 devices, though this works with iPhone 4, iPhone 3GS, iPod touch 3rd gen only. So it's now possible for those with really good vision and some kind of dock to actually use an iPhome/iPod touch as a very mobile computer, especially if they opt for Apple's elegant Wireless Keyboard. I've tested such a configuration, and it works well, though again the iPhone/iPod touch screen is a bit small for serious, long term work. At least for me.
The productivity workstation of tomorrow?
For the latter, Wi-Fi will now stay enabled when the device is asleep so that VoIP calls and notifications can come in. This is sort of an extension to multitasking, and it makes these apps first-class citizens, something that was most definitely not the case before iOS 4. I'm sure AT&T is ecstatic.
This is not technically an iOS 4 feature because you have to download it manually from the Apps Store. But Apple talks it up a lot in its own iOS 4 promotions and events, and the company is clearly pretty proud of its budding eBook reader. Suffice to say that with the porting of iBooks to iPhone/iPod touch, this application picks up a number of features that Kindle users have enjoyed for years, such as auto syncing of place and bookmarks between devices. That said, iBooks is still inferior to the Kindle software on a number of levels, not the least of which is that it's not available on PCs or Macs. Yet.
Apple will deliver iOS 4 to existing iPhone and iPod touch users on Monday, June 21, 2010 and will of course include it with new iPhone 4 devices starting June 24. The iOS 4 update for iPad won't ship until sometime in September, for some reason. But give Apple some credit on the pricing: The iOS 4 update is absolutely free, for all customers, even for those with iPod touches. (Apple previously had to charge a $20 fee for iPod touch updates due to some vague accounting reason. Even vaguer is how or why this charge is no longer required. Still, no complaints here.)
While many believe that Google's Android system is now the one to beat, iOS 4 sends a strong message that Apple is intent on retaining its competitive advantages. This is a nice update to an already impressive smart phone platform, and that's especially true if you have one of Apple's more modern devices, like an iPhone 3GS or iPod touch (late 2009 models). But even those with more antiquated hardware can take advantage of some of the iOS 4 features, and when you factor in the price--absolutely free--and Apple's very aggressive habit of obsoleting old hardware, that ain't bad at all.
From a technical perspective, I think that iOS 4 puts the iDevice world--iPhones, iPod touches, and, eventually, iPads--on par with what's happening over at Google. Looking ahead, Windows Phone 7 still retains its single key advantage--a rejection of the app-based interface metaphor--and that's something Apple will need to address by the next generation iOS release. But Windows Phone 7 will also offer a simplicity that iOS, after four aggressive years of updates, has long since left behind. This is the way of things: As you pile on functionality you inevitably break with the simple interfaces that put you on the map in the first place. Whether this is a boon or boondoggle for Windows Phone 7, however, remains to be seen. There's a fine line between simple and stunted, after all.
We'll see. For now, iOS 4 is a fine update that puts Apple's devices in a rarefied position in the market. I suspect much sales success will follow, but I'm more interested in technical prowess, capability, and usability. And in those key areas, iOS 4 really delivers.