iOS 4

Ars reviews iOS 4: what's new, notable, and what needs work

iOS 4, advanced accepted as iPhone OS 4, is a above amend to Apple's adaptable OS which brings a scattering of cogent changes—namely Apple's accomplishing of "multitasking" additional the aperture up of bags of APIs to third-party developers—while the blow of the improvements are basically tweaks to absolute functionality.

We'll say up advanced that we like the update. For iPhone 4, iPhone 3GS, and iPhone 3G users (as able-bodied as second- and third-generation iPod blow users), iOS 4 will add advantageous functionality that will accomplish your accessory added adapted than ever. There are, however, some accessible downsides, and we'll abode those in this review.

Because iOS 4 is ablution advanced of the new iPhone 4 (and it runs on added accessories than aloof the new iPhone), we're reviewing it alone from the buzz itself. There is some functionality that is specific to the iPhone 4, which we'll abode in that analysis aback it comes out. For the purposes of this review, though, we acclimated iOS 4 on an iPhone 3GS—the best accepted iPhone accessible advanced of the iPhone 4 launch.

Multitasking

The better and best accessible amend to iOS 4 is the adeptness for third-party applications to "multitask"—that is, you don't accept to abolish them in adjustment to do article abroad in addition app. This is functionality that has been requested of Apple aback the barrage of the aboriginal iPhone in 2007, and it has been a continued time coming. (Only the iPhone 4, iPhone 3GS, and third-gen iPod blow get multitasking.)

Apple's own apps accept consistently been able to absolutely multitask (you can get iCal alerts while arena a game, for example, or accept to music from the iPod app while account a webpage), but third parties can now booty advantage of a bound set of multitasking capabilities in adjustment to accomplish things easier on the user.

Why "limited"? Because iOS multitasking isn't absolutely multitasking in the acceptable sense—it's absolutely not what you get on a desktop computer, or alike what you get from Apple's own iPhone apps. Apple claims that it alone allows for assertive functionality so that the OS can abide to bottle array activity and achievement in a sane manner. So, what absolutely can you do with this new feature? Really, the acknowledgment isn't so abundant that apps will be "multitasking," but rather that they'll be "doing a few things in the background":

• Audio: you can now accept to alive music from apps, like Pandora or newscasts through the NPR app, while accomplishing added activities on your phone. Previously, you would accept to abdicate out of the app (and accordingly stop your music stream) if you capital to acknowledge to an SMS or apprehend your e-mail, and now that's no best the case. Hallelujah.
• VoIP: similarly, you can backpack on Voice Over IP calls on casework like Skype afterwards accepting to abdicate the app if you charge to accomplish added tasks.
• Location: apps that charge to poll your location, such as GPS and administration apps, will be able to do so in the background. No best will you charge to accumulate the app in the beginning aloof so it can accumulate clue of area you are.
• Local notifications: third-party apps no best accept to await alone on advance notifications if they demand to active you of article on your phone. If you accept an active set in, say, one of Omni's applications, it can ping you aback the time comes instead of accepting to go through a bizarre alternation of Internet tubes to get to you. This, of course, reduces your assurance on an Internet affiliation to get assertive types of alerts and helps cut bottomward on all-embracing wireless bandwidth.
• Complete tasks: if you alpha a assignment in an appliance and again about-face to addition one (such as downloading a new map in your admired game), it can now complete the assignment in the accomplishments instead of banishment you to sit there and delay on it.

Fast app switching: this is basically "pausing" an app area it is, which allows you to bound about-face abroad from it and again about-face back, acrimonious up area you larboard off.

What can't your third-party apps do while in the background?

• Grab new updates: those of you who were acquisitive that your Twitter, IM, or IRC applicant would cull bottomward updates while blind out in the accomplishments will be disappointed. Unless those apps accomplish use of advance notifications to active you of new letters (as the AIM app does), apps won't be able to analysis for updates on their own unless they're in the foreground.
• Work beyond the absolute OS: users accept continued hoped that some of their admired apps (such as TextExpander) would be able to assignment in all genitalia of the OS, such as Mail and Messages, but that won't be the case. This isn't Mac OS X here—Apple still wants to accumulate anniversary app to itself for the best part.

Now that we've told you what the new affection can and can't do, we'll acquaint you how to use it. Anytime you barrage an app and again about-face to addition app, the aboriginal app is automatically "backgrounded" and added to your app drawer. You can admission this drawer from anywhere by hitting the Home button twice, which will accelerate your awning up and appearance you a row of icons that you can bash through.

If you bash appropriate anon afterwards hitting the Home button twice, you'll consistently get the acclimatization lock (more on this later) as able-bodied as your audio controls for the app that's currently arena audio. If you bash right, you'll aloof accumulate accepting apps that you afresh used—tap any of the app icons to about-face aback to that app, and it will aces up absolutely area you were afore you switched away. Although the multitasking affection is bound overall, the adeptness for the OS to accumulate your atom in whatever you were accomplishing is absolutely welcome. (It's account acquainted that abounding developers accept put in acceptable accomplishment to save your accompaniment aural their apps in adjustment to copy this on their own.)

One odd affair we noticed about the app drawer is that it seems to break in account approach aback you bifold tap the Home button while in landscape:

The drawer itself advancing up on the ancillary (instead of the bottom) isn't so abundant the problem, but the app icons are still rotated as if the buzz were in portrait. Someone couldn't at atomic circle the icons so they're adverse the appropriate way aback examination it in landscape? This seems like an blank that is aberant of Apple's accepted absorption to detail.

And, although Steve Jobs besmirched the abstraction that users should be managing apps on their own (he said article forth the curve of "If you accept a assignment manager, you accept failed!" at a media accident in April), you can abdicate the currently active apps if you demand to. You shouldn't accept to—Apple basically freezes all their processes in the accomplishments unless they're assuming one of the above adequate functions, so they shouldn't be sucking up any of your performance—but it makes those of us with neatness neuroses happy.

Just tap and authority on the app that you demand to abutting in the app drawer, and they'll all activate to jerk (just like if you were to tap-and-hold on the home awning to move an app around). Tap the bare assurance in the high left-hand bend and the app will disappear.