Speaker / earpiece 
 
 Software 
 
 Multitasking 
 
 Fast app switching: You know how you can leave off in Mail halfway through writing a response and go back to exactly where you were? Well that happens everywhere now. When you leave the app, you go back in exactly the same place. And it happens quickly. Fast app switching is essentially like toggling between "paused" applications. This combined with Apple's new app switcher (double tap the home button to bring up your most recently used apps) destroys that annoying iPhone feeling of going in and out and in and out. It just doesn't exist anymore, provided all your apps are up to date, which is going to take some time. It's amazing how much this single feature counts -- it's definitely one of the prime movers here, and it's so simple it's stupid. We would have liked to see options for "favorite" apps or some way to prioritize what you're switching to, but once you get used to this system -- which just puts whatever you've used most recently to the far left -- it makes some sense. 
 
 You know how you can leave off in Mail halfway through writing a response and go back to exactly where you were? Well that happens everywhere now. When you leave the app, you go back in exactly the same place. And it happens quickly. Fast app switching is essentially like toggling between "paused" applications. This combined with Apple's new app switcher (double tap the home button to bring up your most recently used apps) destroys that annoying iPhone feeling of going in and out and in and out. It just doesn't exist anymore, provided all your apps are up to date, which is going to take some time. It's amazing how much this single feature counts -- it's definitely one of the prime movers here, and it's so simple it's stupid. We would have liked to see options for "favorite" apps or some way to prioritize what you're switching to, but once you get used to this system -- which just puts whatever you've used most recently to the far left -- it makes some sense. Task completion: Basically, task completion lets an app do its thing even if you leave it. So if you're uploading or downloading a picture in Evernote or Dropbox, or saving an article in the New York Times app, even if you navigate away, the job is done when you get back to the app. This accounts for a lot of what we think of as multitasking. Most of your apps are just idling -- it's only when you interact with them that it counts. We don't know the boundaries for this API, though it seems to leave a lot of room for creative use. We know it's not just big jobs, it's little ones too -- Colloquy uses this feature to keep you connected to your IRC host. To be honest, that kind of behavior is one thing we thought we wouldn't see in iOS 4, and here it is. Hopefully Twitter app devs and other instant messaging clients will utilize the API in a similar manner. 
 
 Basically, task completion lets an app do its thing even if you leave it. So if you're uploading or downloading a picture in Evernote or Dropbox, or saving an article in the New York Times app, even if you navigate away, the job is done when you get back to the app. This accounts for a lot of what we think of as multitasking. Most of your apps are just idling -- it's only when you interact with them that it counts. We don't know the boundaries for this API, though it seems to leave a lot of room for creative use. We know it's not just big jobs, it's little ones too -- Colloquy uses this feature to keep you connected to your IRC host. To be honest, that kind of behavior is one thing we thought we wouldn't see in iOS 4, and here it is. Hopefully Twitter app devs and other instant messaging clients will utilize the API in a similar manner. Background audio and VoIP: These two are straightforward. The first allows for music playing apps to keep their stream running in the background (and even gives them little widget controls in the app switcher), and the second allows VoIP connections to stay active. That means you can stay on a Skype call and go check your mail, but it also means that the VoIP connection will be aware of incoming calls when you're not actively using an app. Additionally, this API can be used to allow for recording even if you exit an app, as demonstrated effectively in the new version of Evernote. 
 
 These two are straightforward. The first allows for music playing apps to keep their stream running in the background (and even gives them little widget controls in the app switcher), and the second allows VoIP connections to stay active. That means you can stay on a Skype call and go check your mail, but it also means that the VoIP connection will be aware of incoming calls when you're not actively using an app. Additionally, this API can be used to allow for recording even if you exit an app, as demonstrated effectively in the new version of Evernote. Background GPS: Basically, GPS apps can keep running in the background... for obvious reasons. This one will drain your battery if you're not docked -- but who's using a GPS app and not plugging that thing in? Okay, we might be a little guilty of that. Regardless, this will keep your navigation software afloat if you have to take a call, and apparently will let GPS-centric apps like FourSquare check in even if you're not running it in the foreground. 
 
 FaceTime 
 
 Folders 
 
 Mail improvements 
 
 iBooks / iMovie 
 
 What's not in the new OS 
 
 Accessories 
 
 Battery life 
 
 Wrap-up 
 
 As far as video goes, we were definitely impressed by the 720p capture, though there are stability issues with the lens and the all-too-familiar "jellyvision" CMOS issues that tend to rear their head if you're not holding the phone very steady. Still, we can't see carrying around a Flip HD instead of just keeping this in our pocket (though as we said, we'd like to see a higher storage capacity). Everything we shot looked crisp and mostly artifact-free, and we didn't see any hiccups in the 30 FPS rate Apple claims, even in lower light. Adding iMovie to the mix for on-the-fly editing is a nice touch too (more on that in the software section). The video below was shot and edited completely in-phone, so enjoy -- and here's the raw output to download Around front, the VGA camera is... well, a VGA camera. It actually does a fine job of capturing your face during video calls, and worked surprisingly well in low light, but it's not going to win any prizes for being the most advanced shooter on a handset. It does provide for some interesting angle options when it comes to video shooting, and we expect a lot of people will be taking advantage of the weirdly video game-like perspective. All in all, it looks good, but it's pretty utilitarian.We've never had a particular problem with the speaker or earpiece on previous iPhones (well, the speakerphone has never been loud enough for our taste), but it's obvious that Apple has done some work on getting both call quality and speakerphone quality up. Beyond making the phone considerably and consistently louder in both places, the clarity of the iPhone 4 is noticeably improved from the previous generation. If you read our review, then you know that we thought Motorola's original Droid had some of the best sounding components we've heard on a phone, and the new iPhone definitely gives them a run for the money. The first time we took a call on the device we were walking down New York's extremely noisy Fifth Avenue, and right away it was obvious that the secondary, noise-canceling mic was doing some heavy lifting, at least on the other end of the line. Even though sirens were wailing behind us and we were surrounded by chatty shoppers, it was easy to hear our party on the other end, and they could hear us perfectly (unless we were lied to). There's clearly a difference between the sound in the earpiece on the new phone versus the 3GS, and it ranks highly against newer competition like the EVO. As far as the speakerphone goes, it gets loud without distorting or producing cutting midrange, a problem we've noticed on quite a few recent phones. We'd liken the iPhone 4 in quality to something along the lines of the BlackBerry Bold -- a bearable tone even when it gets hot.As with the other revisions to Apple's phone line, the hardware is only half of the story. Along with the iPhone 4 comes iOS 4 , the re-branded iPhone OS which boasts loads of new features, most notably a very Apple-ized version of smartphone multitasking, a video calling feature dubbed FaceTime, folders so you can organize your apps, enhanced Mail, and lots of other nips and tucks -- both big and small -- that refine the company's growing operating system. Additionally, Apple has ported the iPad's iBooks to the smaller screen, and has created a new version of its popular iMovie just for the iPhone 4. Overall, the OS is still very much the same as it's always been, but there are some big changes here that bear investigation.This is a big one, and more than just a little controversial. Since the dawn of apps for the iPhone (remember, way back in 2008?), people have been up in arms about the lack of third-party backgrounding for applications. Sure, you could keep Mail, Safari, iPod, and a few other Apple programs cranking while you used your phone, but those privileges were strictly off limits for third-party devs working on the device. It's arguable that one of the driving forces behind the jailbreaking movement was a desire for this feature -- something a phone as powerful as the iPhone was clearly capable of. Apple's argument has always been that multitasking causes an undue amount of battery drain from phones, and had to be approached with caution, lest we all end up with juiceless phones at high noon. Recently, however, that tune has changed. Apple has -- in true Apple fashion -- "figured out" how to "do multitasking right" -- namely, the company isn't allowing full backgrounding as much as it's allowing a handful of APIs that mimic backgrounding. Things like holding onto a GPS signal, letting music play in the background, staying connected to VoIP calls (or receiving them), and fast switching (basically a way for you to return quickly to exactly where you left off in an app).So, does Apple pull it off? Can this scarce handful of APIs makeup for true backgrounding? In a word: yep.Here's the thing -- this may not be "true" multitasking for a lot of us, but it amounts to multitasking for most of us. That is, it looks, feels, and acts like multitasking, so it's pretty tough to complain about it. In fact: we're not going to complain about it, especially given the fact that some of our favorite apps -- the IRC client Colloquy being one of them -- do just about exactly what we need them to do, all according to Apple's rules and regulations. Previous to the new OS, we'd been jailbreaking our phone just to keep an IRC session running in the background. Now, utilizing some of those new APIs, the Colloquy developers have created an elegant and useful solution that pleases both users and the Cupertino Cops. The point is: it works, it does so bug free, and without a major drain on battery life (quite the contrary... more on that in a moment). We're not saying we liked waiting for this kind of thing to come around, and yes, we'd prefer something more open and flexible -- but this works, and works well.So how is Apple making this magic happen? Here's a breakdown of just exactly what multitasking really means (and feels like) on the new iPhone (and the 3GS):Apple combines these heavy hitters with more familiar tricks, like push notifications, to excellent effect. We know that the hardcore users will cry foul because a lot of this doesn't amount to "true" multitasking, but we also know that often solutions to problems come in different colors. Apple found a way in iOS 4 to solve a pretty good amount of its major problems in this department, and so far what we've seen is very promising. If it's only going to get better from here, we don't mind coming along for the ride. But it better only get better, Apple.If you didn't know anything about video calling, Apple would definitely have you convinced that they just up and invented the concept based on never-aired Jetsons footage judged too futuristic for TV. Of course, the truth is that in lots of other places (and even in the US to an extent), smartphone video calling isn't exactly a new thing. In fact, in much of Europe and Asia, this technology is old hat. But Apple isn't going to let a little thing like facts get in the way of a good marketing play, and in their (slight) defense, no one's effectively brought video calling to the masses just yet. (One of our European editors says that he's gone ten years without seeing anyone make a video call in his neck of the woods.) While this may be an unscientific perspective, it suggests that it's not enough to just have the tech -- the feature needs to be sold to people.So has Apple done it? Maybe, and maybe not. We're certainly impressed by the concept and Apple's willingness to open up their "FaceTime standard" to anyone who wants to get in on the party. That means that developers on any platform -- provided they can meet all the necessary requirements -- can create applications that talk via the protocol (or set of protocols, really). We're also impressed with the tech itself, which feels polished and slick out of the gate. But right now, there's only one way to do FaceTime calls, and that's via the iPhone 4... and only over WiFi, which means that the opportunity to make these calls is pretty limited for now. Additionally, in our testing, we found that you really need to have a good, strong, nearby WiFi signal to hang onto a connection. More than once we had video freeze on us, and we had one fully dropped call because someone went out of the WiFi range, but hey... you need to be in range for even the most basic tasks, so we can't fault Apple too much for that. It does seem clear that the iPhone video chats are moving quite a few bits around, however. What's nice about FaceTime is that unlike Qik or other third-party options for something like the EVO, there's no setup here and it's completely integrated into the dialer of the phone -- meaning the only hangup is whether or not you have decent WiFi.But what is it like? Well in truth, it's actually a teensy bit amazing. Yes, we're a little numb to the PR speak about how game changing it is, but there's still something deeply sci-fi about dialing up a friend and being able to hold this thing in your hand and have a video chat. We did a call with Apple's Greg Joswiak while he was in Paris (see the image above), and when he walked outside and flipped the camera to show us the Eiffel Tower, it was a legitimately weird experience -- a "you are there" moment. As you can see in the call below with USA Today's Ed Baig (his take on the iPhone 4 is right here ), it's a pretty new way to talk to someone, at least for us. Having a random face-to-face conversation with a kid about what he's having for lunch is just the tip of the iceberg -- we can definitely see this feature coming into play in all sorts of ways in our lives.Technically speaking, actually making calls is straightforward; you can switch to a FaceTime chat while you're already connected, or you're given to option to launch right into a FaceTime connection. We were a little surprised by the fact that you can only mute the audio on your calls; if you want the video off, you need to cover the lens in the old fashioned way -- with your hands.All said, it's a fascinating inclusion, and we've got a sneaking suspicion that Apple intends to do more than just basic calls with this. Obviously the addition of conference FaceTime sessions would be huge, and we're also looking forward to using the function on a 3G network -- it's nice to have a chat from your house, but what would really be great is taking these kinds of conversations out into the wide world. We think that coupled with active development for clients on lots of platforms (not just the iPhone) will make FaceTime much more interesting -- it's a curiosity right now, but it could be something else entirely with a little time and elbow grease.What can you really say about folders? Basically: it's about time. We're happy that Apple has seen the light and included something like this in iOS 4, and the implementation is elegant enough, but it would have been nice to store more than 12 items at a time. As it stands, if you have a lot of one kind of app, you're going to end up with a group of folders in the same category. We have a second "Games" folder, but some of you out there will have more like six or seven of those. That helps the problem, but doesn't solve it completely. We get why Apple made this decision -- likely a desire to keep it simple -- but it would be nice to be able to make the room if you wanted it.For a lot of us, the new tweaks to the iPhone's Mail app have seriously been a long time coming. Among the major improvements in iOS 4 are a unified inbox and threaded messaging (finally!) -- both of which have made dealing with email on the iPhone a considerably more enjoyable experience. We still think that the mail client is lacking in comparison to Gmail, but that has more to do with our addiction to Gmail than anything else, we suspect. Overall, Mail feels much more complete now, and Apple has solved the same problem in Mail that it had with app switching -- that feeling of constantly jumping into and out of your inboxes.This isn't a barnstormer, but it's a nice inclusion. If you've used iBooks for the iPad, the experience is about the same... just smaller. There's not a ton to say about it, except that in addition to lots of other great book apps on the iPhone, Apple has now given you its own. We still don't think it stacks up to Amazon or Barnes & Noble in terms of selection, though the presentation is better in many ways, and it will sync your notes and bookmarks across platforms.iMovie, on the other hand, is something new entirely. We can't say we didn't see this one coming since Apple just added video recording and editing to its arsenal with the introduction of iPhone OS 3 and the 3GS -- but this takes things one step further. The $4.99 app gives you access to more advanced features, like a (very) limited selection of transitions between clips, the option to add audio to your videos, plus a handful of themes and titling effects. We found it to be extremely capable for fast edits, though everything is pretty sandboxed here, so while you do have the most basic editing tools, things like splitting a clip can be a little bit of a hassle. Since you can only edit the beginning and end of a snippet, if you want to split something into multiple parts you have to drag the clip into your edit repeatedly and then scale the start and finish points for each one. It can be a pain if you're doing lots of jump cuts -- though we don't expect everyone to be making the next Casino on this thing... though, someone probably will, right? For a few bucks, it's definitely worth having, and we expect that after a few people start using the thing, Apple might be prompted to add a few more options.It's not all wine and roses as far as we're concerned. While Apple has made huge strides in many areas here, this wouldn't be an Engadget review if we didn't have our nitpicks. In particular, we still cannot understand or accept the company's approach to notifications. We're at version 4 of this OS, and we're still plagued by these intrusive, productivity-freezing alerts. If you're as busy as we are, then you know what it's like to get invite after invite for your calendar, text messages, and push notifications that just stall the phone out. While every other modern OS-maker has figured out an elegant way to deal with notifications (including the forthcoming Windows Phone 7 ), Apple clings to this broken system. Why? We can't really say. We find it hard to believe that there aren't folks in Cupertino who feel the way we do -- in fact, we're sure of it. Maybe that explains the hiring of Palm's "notification guru" Rich Dellinger. We sure hope!The other thing that's driving us crazy is the lack of widgets. Apple almost gets there with its new extensible music player controls, but there are still no good solutions for glanceable information on the iPhone. We'll admit that it's better now that fast app switching is in play, but we'd still like that weather icon to actually show us the temperature where we live. Is that too much to ask? The competition seems to have this one licked -- we'd really like to see Apple take a stab at it.It wouldn't be a new iPhone without some accessories, but Apple has kept it tidy. The company is offering a new dock, of course, for twenty-nine of your US dollars (that's $29), and a selection of colorful "bumpers" that protect the phone for the same price. We've got a few bumpers in-house, and while we're not really big fans of the way they look or feel, they do seem to protect the phone pretty well. On that note, we've actually seen the iPhone 4 tossed with and without a bumper across a room (one hit a wall) with no issue, and we dropped ours pretty hard from about two feet up onto tile with nary a scratch.This is a big one for many people, and we have some fairly surprising news to report. The battery life on the iPhone 4 has been outstanding thus far, exceeding our expectations for longevity during testing. We've only had a short time to use the phone, but in the week or so we've been carrying the device as our main phone, we've had pretty amazing results under normal to heavy use. In fact, we managed to squeeze more than 38 hours -- yes, 38 hours -- of life out of a single charge using the phone as we normally would. We're talking calls, some gaming, lots of push email and calendar invites, playing music over Bluetooth in the car, and just general testing (like downloading new apps, rearranging icons, tweaking settings). We went from 10:30AM on a Saturday morning till 1:00AM on Monday without needing to charge the phone. Of course, it switched itself off just after the clock struck 1, but it was thrilling -- like that episode of Seinfeld where Kramer and the car salesman see how far they can get in a car with the tank on E. Sitcom references aside, the battery life seems markedly improved in the iPhone 4, and why not? It's got a much larger battery coupled with that iPad-powering A4, which has already shown that it can sip rather than gulp power.Once the rest of the team has their iPhones in hand, we'll do some hardcore battery life testing and see what we come up with, but we think under pretty active use, the iPhone 4 blows Apple's previous generation phone out of the water, and makes a lot of the competition look downright needy.We're not going to beat around the bush -- in our approximation, the iPhone 4 is the best smartphone on the market right now. The combination of gorgeous new hardware, that amazing display, upgraded cameras, and major improvements to the operating system make this an extremely formidable package. Yes, there are still pain points that we want to see Apple fix, and yes, there are some amazing alternatives to the iPhone 4 out there. But when it comes to the total package -- fit and finish in both software and hardware, performance, app selection, and all of the little details that make a device like this what it is -- we think it's the cream of the current crop. We won't argue that a lot of this is a matter of taste -- some people will just prefer the way Android or Symbian works to the iPhone, and others will be on the lookout for a hardware keyboard or a particular asset that the iPhone 4 lacks -- but in terms of the total picture, it's tough to deny that Apple has moved one step past the competition with this phone. Of course, in the hyper-accelerated smartphone market where the Next Big Thing seems to always be just around the corner, it's anyone's guess how long they keep that edge. ||||| Just three years ago, Apple wasn't in the mobile-phone business at all. Since then, its game-changing iPhone has become the most influential smartphone in the world. Now, on June 24, the company will roll out the fourth generation of the device, called the iPhone 4. 
 
 Walt Mossberg answers viewer questions about Apple's new iPhone 4 and breaks down the devices new and improved features. Plus, why you won't be able to get an iPhone4 from AT&T; until next week. 
 
 Apple's iPhone 4: Great, But Needs New Network 7:23 Three years ago, Apple wasn't in the mobile phone business at all. Now, it's rolling out the fourth generation of its game-changing iPhone. WSJ's Walt Mossberg reviews the iPhone 4, which he says has a number of cool new features as well as a "big downside." 
 
 While attractive, capable new smartphones emerge regularly from competitors, a new iPhone deserves special attention for two reasons. First, the device lies at the center of a huge ecosystem of 225,000 apps, plus popular related gadgets like Apple's iPod Touch connected media player and iPad tablet, which collectively are approaching 100 million units sold. Second, the iPhone's multitouch, gesture-based interface; elegant Web browser; sophisticated music and video playback; and other features have been emulated on many competing devices, so what Apple does affects the whole industry. 
 
 I've been testing the iPhone 4 for more than a week. In both hardware and software, it is a major leap over its already-excellent predecessor, the iPhone 3GS. 
 
 It has some downsides and limitations—most important, the overwhelmed AT&T network in the U.S., which, in my tests, the new phone handled sometimes better and, unfortunately, sometimes worse than its predecessor. I'll get into that below. But, overall, Apple has delivered a big, well-designed update that, in my view, keeps it in the lead in the smartphone wars. 
 
 The iPhone 4 is a dramatic redesign. It manages to pack a radically sharper screen; a second, front-facing camera; a larger battery; a better rear camera with flash; and a faster processor into a body that is 24% thinner, a bit narrower, and retains the same length and weight as its predecessor's. In fact, Apple claims that the iPhone 4 is the world's thinnest smartphone and sports the world's highest-resolution smartphone screen. 
 
 With the front-facing camera, and clever new software called FaceTime, Apple has brought simple, high-quality video calling to mobile phones, albeit, for now, only over Wi-Fi and only among iPhone 4 owners. In multiple tests, this feature worked very well for me and is a classic example of the value of having one company do integrated hardware and software. 
 
 In addition, the iPhone now includes an updated operating system—which also can be installed free on the prior model—that introduces catch-up software features such as limited multitasking (the ability to run apps simultaneously); folders for grouping related apps; and, for email, a unified inbox for multiple accounts and the ability to present messages as threaded conversations. This software is called iOS4. 
 
 The iPhone 4 will cost the same as the iPhone 3GS: $199 for a model with 16 gigabytes of memory and $299 for 32 gigabytes, with a two-year contract from AT&T. The 3GS model will drop to $99 with a two-year contract and 8 gigabytes of memory. 
 
 Design 
 
 First Look at iPhone 4 View Slideshow Associated Press 
 
 Physically, the iPhone 4 is attractive and feels great in the hand. Even the back is now clad in glass, which Apple claims is a superstrong variety 30 times tougher than plastic. I dropped it several times from a few feet onto a hard surface with no problem, and it acquired no scratches at all in my testing, even though I didn't use a case or coddle it. 
 
 Although it is the same weight as its predecessor, the iPhone 4 feels denser and tighter—more like a fine possession than a disposable gadget. It still looks like an iPhone, but it manages to make the 3GS appear bulbous by comparison. 
 
 While its 3.5-inch screen, once considered huge, is now smaller than those on some other smartphones, the high resolution packs in a lot of material and makes text appear almost like ink on fine paper. The software is simply richer looking and smoother to use than on competing phones I've tested, with fewer confusing menus and settings, and far more apps. 
 
 Screen, Voice, Battery and Camera 
 
 Always brilliant at marketing, Apple has dubbed its new screen the "Retina display." At a resolution of 960x640, it has four times the pixels of its predecessor and displays a whopping 326 pixels per inch. I don't know how it compares with the human retina, but I do know that, just as Apple claims, text on the screen shows no jagged lines, even when expanded to giant size. 
 
 Voice quality was quite good, even on long speaker-phone calls, and data performance over Wi-Fi was excellent. Video and audio streamed from the Web played smoothly. 
 
 Apple claims longer battery life for most functions—seven hours of talk time, for instance, versus five hours on the earlier model. I didn't perform a precise battery test, but, even in heavy use, the iPhone 4's battery never reached the red zone on a single day of my tests. 
 
 The new rear camera is another big plus. My test pictures came out sharp and clear, even in low light and close-up situations. It isn't the best cellphone camera I've tested, but it is a big improvement. 
 
 The iPhone 4 records video in high definition and, in my tests, these videos came out very well in most conditions. Apple also is selling for $5 an iPhone version of its Macintosh video-editing program, iMovie, for editing the videos. 
 
 FaceTime 
 
 An iPhone Snapshot Positive Improvements Higher-resolution display with 960x640 pixels 
 
 Improved built-in camera with flash 
 
 Front-facing camera and FaceTime video chatting software 
 
 Multi-tasking 
 
 Unified inbox for multiple email accounts 
 
 Improved battery has 7 hours of talk time 
 
 Folders for organizing apps Negative Multi-tasking is limited 
 
 AT&T reception gets mixed results 
 
 FaceTime video chatting only works with other iPhone 4s and over WiFi 
 
 Video calling is one of this device's best features. As noted, it currently requires an iPhone 4 and Wi-Fi connection on both ends, though Apple says it is making the technology free to others and hopes to have millions of compatible devices. There is no setup and nothing to learn. You just press a FaceTime button, and if the other person accepts the invitation to talk face to face, his or her image appears, with your own image showing in a small corner window. 
 
 You can tap an icon on the screen to swap the front camera for the rear one, so you can show your caller around the room, or include other people near you who are behind the phone. 
 
 You can even begin a video call as an audio cellular call, push a button, and switch it to a Wi-Fi FaceTime call. It worked great for me, except for a couple of brief freeze-ups. 
 
 Multitasking 
 
 After years of complaints, Apple finally has brought multitasking to the iPhone. But it has done so in a limited way that won't please everyone. On the iPhone 4, multitasking doesn't mean every app can work fully in the background. To prevent a disastrous drain on battery life, Apple has allowed only certain apps to fully multitask. These include streaming audio services like Pandora, which keep playing music from the Web while you do other things, and voice-prompted navigation apps, which keep working while you're on a call. Others that fully work in the background include Internet calling apps, and those that perform long downloads. 
 
 But some logical candidates, such as Twitter and Facebook, merely pause in place when you switch away from them. You can get back to them quickly, and they update more rapidly than before, but they don't constantly update in the background. They only wake up in the background if you have set them to notify you of an update, and then only for a limited time. Apple says constant fetching of hundreds of social-networking updates in the background would kill the battery too quickly. 
 
 In fact, for many scenarios, such as games, Apple's version of multitasking is really just fast switching among open apps that save their place. And, even to achieve this, the apps must be updated. For some users, this limited version of multitasking will be a disappointment. 
 
 To use multitasking you just press the iPhone's home button twice and a row of icons representing running apps appears. Click on the one you want and, if it has been updated for the new operating system, it will appear just as you left it. 
 
 Multitasking also will work on updated iPhone 3GS models, but not on models older than that. 
 
 Apple 
 
 Folders 
 
 Because iPhone users can easily accumulate hundreds of apps, it can become difficult to organize them. So the new iPhone OS now allows you to group them into folders. For instance, I grabbed the icon for The Wall Street Journal app, dragged it on top of the one for the Washington Post app, and a folder was instantly created called "News," based on the apps' built-in categories. You can change the name to anything you like, or alter or disassemble the folders. 
 
 The Big Downside 
 
 The most important downside of the iPhone 4 is that, in the U.S., it's shackled to AT&T, which not only still operates a network that has trouble connecting and maintaining calls in many cities, but now has abandoned unlimited, flat-rate data plans. Apple needs a second network. 
 
 Both Apple and AT&T told me they worked to make the iPhone 4 do a better job with AT&T's network. For example, the phone itself is surrounded by a prominent stainless-steel trim piece that acts as a large antenna. And Apple said it also tuned the phone to try to grab whatever band on the network was less congested or less affected by interference—to stress the quality of a signal over its raw strength. AT&T said it, too, made some changes to its network with the new iPhone in mind. 
 
 But, in my tests, network reception was a mixed bag. Compared with the previous model, the new iPhone dropped marginally fewer calls made in my car, both in Washington and in Boston, and was much louder and clearer over my car's built-in Bluetooth speaker-phone system. 
 
 Yet, in some places where the signal was relatively weak, the iPhone 4 showed no bars, or fewer bars than its predecessor. Apple says that this is a bug it plans to fix, and that it has to do with the way the bars are presented, not the actual ability to make a call. And, in fact, in nearly all of these cases, the iPhone 4 was able to place calls despite the lack of bars. 
 
 However, on at least six occasions during my tests, the new iPhone was either reporting "no service" or searching for a network while the old one, held in my other hand, was showing at least a couple of bars. Neither Apple nor AT&T could explain this. The iPhone 4 quickly recovered in these situations, showing service after a few seconds, but it was still troubling. 
 
 Just as with its predecessors, I can't recommend this new iPhone for voice calling for people who experience poor AT&T reception, unless they are willing to carry a second phone on a network that works better for them. 
 
 For everyone else, however, I'd say that Apple has built a beautiful smartphone that works well, adds impressive new features and is still, overall, the best device in its class. 
 
 —Find all of Walt Mossberg's columns and videos online, free, at the All Things Digital Web site, walt.allthingsd.com. Email him at mossberg@wsj.com. ||||| Advertisement Continue reading the main story 
 
 
 
 
 
 
 
 Apple’s new iPhone, its fourth in four years, reaches stores on Thursday. Ordinarily, this is where you’d expect to find a review of it. But honestly — what’s the point? 
 
 The iPhone 4 is already a hit. AT&T; says that it received 10 times as many preorders as it did for the iPhone 3GS last year. On the first day of taking orders, Apple processed 600,000 requests — before its ordering system, and AT&T;’s, descended into chaos. 
 
 In short, the public seems to be perfectly capable of sniffing out a winner without the help of tech critics. 
 
 On the other hand, the new model won’t do anything for people who detest the iPhone. It wouldn’t matter if the new iPhone could levitate, cure hepatitis and clean your gutters; the Cantankerous Committee would still avoid it. 
 
 Despite the strong initial, positive reaction, this must still be a nerve-racking time to be Apple; the iPhone is no longer the only worthy contender. Phones running Google’s Android software are gaining rave reviews and packing in features that iPhone owners can only envy. The Android app store is ballooning, multiple phone makers are competing, and Google updates the software several times a year. Apple releases only one new model a year, so the new iPhone had better be pretty amazing to compete. 
 
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 It is. 
 
 The first thing you notice is the new shape. Despite a beefier battery (16 percent more likely to last a full day), a faster processor and upgraded everything, the new model is still noticeably thinner and narrower than before. How is that possible? In part, the trick was squaring off the back. It’s no longer gracefully curved — a design that, if you think about it, created wasted space around the rectangular components. The new iPhone is two glass slabs, front and back, wrapped by a stainless-steel band. 
 
 The result is beautiful, and since there’s no more plastic, it feels solid and Lexus-like. But it no longer feels like a soothing worry stone, and it’s now impossible to tell by touch which way it’s facing in your pocket. The new metal mute and volume buttons are much stiffer. Still, Apple says the iPhone 4 is the world’s thinnest smartphone, and most people will approve of the trade-offs. 
 
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 The new phone uses the same custom chip that’s in the iPad; it’s really, really fast. It makes a difference every time you tap the touch screen. 
 
 It’s not the first phone with both a front and back camera. It’s not even the first one to make video calls. But the iPhone 4 is the first phone to make good video calls, reliably, with no sign-up or setup, with a single tap. The picture and audio are rock solid, with very little delay, and it works the first time and every time. This feature, called FaceTime, is pure Apple. 
 
 However, you can enjoy this classic “show Grandma the baby” fantasy only if you and Grandma both have the iPhone 4, and only when you’re both in strong Wi-Fi hot spots. Both limitations may change in time; other software companies are free to create FaceTime-compatible programs for other gadgets. And Apple implies that next year, you’ll be able to make such calls over the cellular airwaves. Clearly, Apple is giving its ball and chain, AT&T;, time to get its network ready. 
 
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 The new screen, with greater contrast, is excellent. It packs in four times as many pixels as before; at 326 dots an inch, it’s now the sharpest phone screen on the market. Now, “the screen isn’t sharp enough” wasn’t exactly a common iPhone complaint before. But it’s easy to see, and appreciate, the improvement in clarity of text, pictures and videos. 
 
 There’s a new 5-megapixel camera, too — better, though it’s still no rival to a real camera. The actual moment of photo-snapping is an instantaneous affair now, freed of the take-your-time sluggishness of last year’s model. Apple has finally deigned to give us a small, bright LED flash, too. You can make it stay on when you’re filming — a convenient video light for very close-range subjects. 
 
 Speaking of video: the new iPhone takes great-looking 720p high-definition video; now there’s the equivalent of a Flip camcorder in your phone. 
 
 Furthermore, for $5, you can install iMovie for iPhone. This little app lets you trim and rearrange video clips, add music and credits, drop in photos with zooming and cross-fades, and then post the whole thing directly to YouTube. 
 
 Frankly, the whole concept sounds a little ridiculous; video editing on a phone? You might as well introduce Microsoft Excel for Hearing Aids. 
 
 But you watch. The way life goes, some iPhone production will win at Cannes next year. 
 
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 Now, peculiar as it may sound, phone calls have always been the iPhone’s weak spot. It took too many steps to dial. Audio quality wasn’t state-of-the-art. And from Day 1, dropped calls in several big cities have driven people there wiggy. 
 
 With the iPhone 4, Apple tried to relieve the wigginess. Sound is much better on both ends of the call, thanks in part to a noise-canceling microphone and an improved audio chamber (which also helps speakerphone and music sound). The stainless-steel edge band is now part of the antenna. The new phone is also better at choosing the best channel for connecting with the cell tower, even if’s not technically the strongest one. (Ever had four bars, but a miserable connection? Then you get it.) 
 
 Does any of this mean no more dropped calls in New York and San Francisco? No. But there do seem to be fewer of them. 
 
 The even better news is the new operating system, now called iOS4, which became available this week, free to owners of recent iPhone and iPod Touch models. (Apple dropped the word “iPhone” from the OS’s name because it also runs the iPad and the iPod Touch.) 
 
 Three big-ticket features in this software upgrade make a huge difference. First, multitasking. 
 
 Apple has consistently maintained that running several programs at once eats up the battery. So iOS4 permits multitasking of certain important functions — for example, Internet radio can keep playing, and GPS apps can keep updating, while you work in other programs. Other apps go into suspended animation when you switch out of them. They use no power and cost you no speed, but you don’t have to wait for them to start up when you return to them. 
 
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 Second, when you give the Home button a quick double-press, a new app switcher appears at the bottom of the screen. Here are icons for all your recent apps (including the ones you suspended). After three versions of iPhones, you can finally jump directly from one app to another without a layover at the Home screen. 
 
 The third big change: you can now file your apps into folders. (You drag one icon atop another to create a folder containing them both.) Each folder can hold 12 icons, meaning that download-aholics can now install 2,160 apps on a single iPhone. (Well, it’s a start.) 
 
 Those over 40 can now bump up the type size for e-mail, notes, text messages and address book entries. The Mail app can group your messages into threads (back-and-forths on a single subject), and you can view all your e-mail accounts in a single Inbox. A new spelling checker lets you tap an underlined word to see correction suggestions. 
 
 The new iPhone software, in other words, is sweet and free, and you should not hesitate to get it. 
 
 The new iPhone itself is sweet but not free. The 16-gig model costs $200 (the 32-gig model costs $300), but only if you’re a new customer or an existing iPhone owner whose contract expires this year. (For more on prices, plans, tethering and other gory details, see my post Wednesday at nytimes.com/pogue. Disclosure: I’m the author of an iPhone how-to book, written independently of Apple, which I’m updating.) 
 
 Now, the iPhone is no longer the undisputed king of app phones. In particular, the technically inclined may find greater flexibility and choice among its Android rivals, like the HTC Incredible and Evo. They’re more complicated, and their app store not as good, but they’re loaded with droolworthy features like turn-by-turn GPS instructions, speech recognition that saves you typing, removable batteries and a choice of cell networks. 
 
 If what you care about, however, is size and shape, beauty and battery life, polish and pleasure, then the iPhone 4 is calling your name. 
 
 But you probably didn’t need a review to tell you that. ||||| Apple iPhone 4: Hands-on review 
 
 Photo: Dean Putney, shot on a Canon SLR 
 
 The fourth incarnation of Apple's iPhone is an incrementally improved, familiar device—not a new kind of device, as was the case with the recent introduction of iPad. Yes, the notable features with iPhone 4—both the device and the iOS4, which came out yesterday in advance of the iPhone itself—are mostly tweaks. But what tweaks they are: Apple's focus on improvement is as much key to the quality of its products as innovation. Still, there's one flaw it can't completely eliminate: the unreliable quality of calls placed over AT&T;, which remains the iPhone's only U.S. carrier. 
 
 THE FORM FACTOR 
 
 
 
 Thanks to a boy and a bar and a blog, we've already known for some time what the iPhone 4 would look like. The squared-off, thinner, steel-and glass form is more masculine, more substantial. Like a really hot designer watch. There are bevels and grooves and linear details that didn't exist before. It feels really nice to hold. Once my hand got used to it, the 3GS body felt more like a toy, and I didn't much feel like holding it anymore. 
 
 The display is a huge leap forward. It's really crisp, and hues are more true. Side by side, the 3GS display and the iPhone 4 display show that the earlier device gives off warmer hues, more peach/red/yellow casts. The iPhone 4 seems more true to life. This is particularly noticeable when you are reading large stretches of text, or comparing one photo on both devices, side by side. On iPhone 4, whites are whiter, blacks are blacker, and the fonts really pop. It makes long reading sessions much more comfortable, and reading things in low light and high light environments are easier than before. 
 
 The iPhone 4 face and back side are made from "aluminosilcate glass," which Apple says has been "chemically strengthened to be 30 times harder than plastic." Fighting instinct (my... precious!)I banged it on the side of metal tables, attempted to scuff it on the floor, and it did not sustain scratches as my iPhone 3GS and first-edition iPhone have. Granted, I didn't take a hammer or keys to it, and I don't know "Will It Blend"—I felt too protective—but this is clearly a much sturdier face. This also explains why Apple is only selling those little "bumpers" now, to snap around the edges, instead of older style cases that also protect the face and back of the device. The metal volume and mute/vibrate buttons feel nice (and are echoed in metal details on those little snap-on bumpers.) 
 
 BATTERY LIFE 
 
 
 
 Battery life has been an Achilles' heel with earlier versions of this device. It's noticeably improved, and that's a good thing, because much of what this device can do will require more power, over more time. You're gonna want more battery. With light use, but with 3G data and WiFi turned on the whole time, I got a full 4 days of battery life. With very heavy video recording and playback, instant messaging, email and data tethering over 3G, I got a full day of battery life. I didn't have enough time before this review to do careful benchmark testing against Apple's claims, so I can't provide specific percentages, but it felt like the battery life was a good 20-25% meatier. 
 
 Photo: Xeni at Venice Skate Park with Drew, 11 (L), and Kiko, 8 (R). Shot by Julian Bleecker on a Nikon SLR 
 
 Apple promises up to 7 hours of talk time on 3G and 14 hours of talk time on 2G, Standby time of up to 300 hours, up to 10 hours of solid use on Wi-Fi, up to 10 hours of video playback, and 40 hours of audio playback. 
 
 Compare that with the stats promised for Apple's iPhone 3GS: up to 5 hours talk time on 3G, up to 12 on 2G. Up to 5 hours of internet use on 3G, up to 9 hours on Wi-Fi. Up to 10 hours of video playback, and 30 hours of audio playback. 
 
 THE PHONE STUFF 
 
 Gadget bloggers and tech reviewers have made much over the built-in antenna placement, and speculation that the body construction allows for greater signal conductivity. 
 
 I rode my bike around town with iPhone 4, iPhone 3GS, and the original iPhone, and observed signal strength differences. 
 
 Here's the thing: 
 
 AT&T; still sucks, and the best engineering out of Cupertino won't change that. 
 
 AT&T;'s network includes black holes and Bermuda Triangles in many places around my town, Los Angeles. Even where signal strength was terrific, dropped or garbly calls did still occur sometimes with this new iPhone. But a little less often. 
 
 Overall performance and reception capabilities with iPhone 4 did seem improved, during my limited tests. The connectivity improvements engineered into this device seem to help you make the best of a very imperfect carrier (and, of course, none of them are perfect). 
 
 Standing in one familiar trouble spot that used to drive me crazy, I often had one or two "signal strength" bars on the first-gen iPhone, maybe one or two more bars on the 3GS, and 4 or 5 bars on iPhone 4. 
 
 Bottom line: I think the engineering is better. But issues of call quality and dropped calls will not be completely gone with this improved device. As we're now four hardware iterations in, I believe that has everything, or nearly everything, to do with the carrier. 
 
 IS IT SPEEDY? 
 
 
 
 Quite. Unlike prior editions, this one uses Apple's A4 processor, which is also present in Apple's iPad. Huge difference in responsiveness, when comparing identical tasks between iPhone 4 and the 3GS or other prior editions. 
 
 FACETIME 
 
 
 
 Video calls are cool. Yes, video calls with Skype and video chat with AIM, iChat, and Google are a well-established part of our internet experience. But FaceTime will open up "video phone calls" to many more users. Here's how it works: using the phone feature, initiate a phone call to someone else who is also using an iPhone 4. A "FaceTime" option will be present for both users, on both ends, and if both opt to initiate FaceTime, you'll be viewing video from each other as you talk. 
 
 iPhone 4 offers the ability to switch the orientation of the camera input, from one side to another, so if you and I are talking I can show you my face, looking into the device right back at you on the other end of the FaceTime call, or I can tap the "switch camera orientation" icon on my screen to show you the sunset on the beach where I'm standing. Well, as long as there's WiFi on the beach: currently, AT&T; won't allow FaceTime over 3G. 
 
 Apple says it will open the Facetime API to developers, which should make for some interesting interfaces between iPhone and social networking or chat services. 
 
 The iPhone 4's camera offers much more detailed shots than before, and performs better in poor lighting conditions. 
 
 CAMERA 
 
 
 
 (Click to view more photos shot with iPhone 4 in this Boing Boing gallery) 
 
 
 
 Reviews of iOS4 have noted that installing the upgrade on 3G iPhones zooms up shutter speed significantly. This is true. And on the iPhone 4 hardware itself, speed and sensitivity with iOS4 on the iPhone 4 itself become nothing short of stunning. I experienced far fewer "lost moments," those dead shots that happen when you've tried to grab just the right instant, and instead you end up with a photo of several instants after the right instant. I brought my iPhone 3GS and iPhone 4 to the Venice Beach skate park, to take shots of fast-moving skaters in those magical aerial moments, just before a swan-dive into the belly of the bowl. With earlier iPhones, man, just forget it. You're using the wrong device. Response is too sluggish for good odds on getting good action shots. But with iPhone 4, I was able to tap-tap-tap in rapid succession, or tap once at just the right instant, and bring home some real trophy jpegs. 
 
 Another strong point of the new version of iPhone's camera is the ability to make better sense of high, low, and medium light within one shot. When you touch on an area of the camera's view to focus, the iPhone automatically senses factors such as exposure, and auto-adjusts for you based on the selected focal point. 
 
 There was a tendency on iPhone 3GS and earlier to get overly dark, or overly blown-out shots when an image incorporates bright whites and dark darks. iPhone 4 is smarter in this regard. 
 
 iPhone's built-in flash is a welcome addition, and will no doubt lead to a proliferation of attractive, boozed-up people in better-lit nightclub snapshots on Facebook (and a new generation of wannabe Cobrasnakes). 
 
 Three options with the flash: on, auto-flash, or off. We're still talking about a tiny flash on an iPhone, so it doesn't perform like a pro flash on a $2500 SLR camera (you're only going to be able to illuminate so far), but it's quite a start. I was able to get intelligible shots of a completely dark room, where without the flash, I'd get nothing but black. One thing I haven't tried yet, which I do with my point-and-shoot digital cameras: making DIY "gels" for the flash. Scotch tape, maybe embellished with highlighter pen ink for rose, yellow, or other human-friendly gel colors. 
 
 At an L.A.-area skate park, Kiko, 8, and Drew, 11, mug for a photo. Taken with iPhone 4 
 
 VIDEO 
 
 
 
 (Click here to watch sample video clips shot with iPhone 4) 
 
 
 
 I'm very, very excited about the video capabilities in iPhone 4. I've spent the last few years of my life working in web video, so forgive me if I "squee" here. The higher definition video [720p] is spectacular, and far better in quality than what was possible with iPhone 3GS (or, as far as I've seen, with any smartphone). You have to be mindful of that camera orientation switch option noted above with FaceTime: when you shoot video out of one side of the device, you get lower-resolution 640 x 480 footage, and when you shoot out of the other side, you get far higher-res 1280 x 720. As with the still camera function, you can tap an area to focus in, even while you are shooting. Video is saved and exported as h.264 QuickTime, and you can email, MMS, or publish to YouTube right from the iPhone. 
 
 LOCATION TAGGING FOR PHOTOS AND VIDEOS 
 
 
 
 The ability to browse what's in your photo and video library by the location where you shot those items is new, and really fun. I took a bike ride from my office to the beach, and from there down a long bike path along the coast to another town. I shot photos and videos along the way. When I arrived back at the office, I was able to view those clusters of media on a map, and tap the red "pushpin" to view everything I'd shot at the skate park, everything I'd shot at the pier, and so on. 
 
 IMOVIE 
 
 
 
 The iPhone 4 ships is released alongside a mobile version of iMovie ($5), so you can edit clips into iMovie projects with transitions, music beds, stylized or simple transitions, and templated themes ("travel postcard," for instance). Export your final product at medium (360p), large (540p), or HD (720p). 
 
 Video snobs may pooh-pooh the notion of editing on a mobile device (which requires a vastly more simplified and less powerful editing toolkit than one has with FinalCut Studio on an 8-core Mac Pro), but hey, a few years ago these same people were also pooh-poohing the notion of shooting video on a mobile device. 
 
 What this means to me: if I'm traveling, I can shoot, edit, and produce little reports or impressionistic video vignettes from the field without having to have even a laptop. That is a very big deal for some people (fine, by "some people," I really mean, "me"). And for non-videobloggers, it means you'll now be getting lots more annoying (but visually good quality) home movies of your relatives' Hawaiian vacations in your in-box. 
 
 When you're video editing on the iPhone 4, there's a theme sound library to work with, and you can even add songs from your iTunes/iPod library as music beds (ahem cough awesome but surprising, given the possible copyright conflicts ahem cough). 
 
 ORIENTATION LOCK 
 
 
 
 Thank you Jesus. At last. Orientation lock on the iPhone, like we have on the iPad. If you're reading Boing Boing in bed, just double-press the "home" button, then swipe that menu bar all the way to the left, and you can lock the display in portrait mode so it doesn't switch direction on you when you roll over or sit up or whatever. I wish you could also lock it in landscape mode. This would be especially handy for videos or gaming while you're passed out drunk in the gutter or relaxing on your couch at home. 
 
 IBOOKS 
 
 
 
 Apple's iBooks—the store, storage, and digital book reading application—works pretty much here like it does on iPad. There are some additional new abilities, like the ability to highlight and add notes. Given what my own personal reading and device usage habits are, I don't know that I'll personally be spending a ton of time reading iBooks on iPhone, but I suspect that others will be awfully excited about the ability to read one book on iPad, laptop or desktop Mac, and iPhone, and start where you left off at any given device. 
 
 MULTITASKING 
 
 
 
 As noted in early iOS4 reviews, multitasking is here, and feels long overdue. There are limits. You can't multitask everything with everything, but the ability to check email and Twitter while I'm on a conference call, or play music while I'm reading a blog, seems natural now (and didn't result in crashiness). 
 
 Double-click the home button to swap between open apps. Holding down the home button for a few moments gets you voice control, as with earlier versions. Touching the home button once, briefly, lets you search iPhone. 
 
 TETHERING 
 
 
 
 It worked flawlessly over Bluetooth, using AT&T;'s 3G, when the cable modem and wireless network in my office happened to be down for a while. What more do you want? It worked when I wanted it to work. 
 
 THE GYROSCOPE 
 
 
 
 I didn't have an opportunity to make use of the additional motion sensitivity that iPhone 4 offers over its predecessor, with the built-in gyroscope. So I can't say much about it, other than the fact it's there. But I'm sure that as the iPhone 4 makes its way out into the wild, developers of augmented reality applications and games will produce products that use this ability to enrich a variety of experiences. To me, those augmented reality possibilities are particularly exciting. 
 
 
 
 Would I buy it? Yes. 
 
 Apple: iPhone 4
– The iPhone 4 hits tomorrow, and tech reviewers everywhere are incredibly impressed. Here's what they're saying: The iPhone 4 is “a major leap over its already excellent predecessor,” writes Walt Mossberg of the Wall Street Journal. The new features work very well, and the redesign “manages to make the 3GS appear bulbous by comparison.” David Pogue of the New York Times almost doesn’t bother reviewing it. “What’s the point?” he writes. They’ve already sold tons of these. “The public seems perfectly capable of sniffing out a winner without the help of tech critics.” But for the record, yes, the iPhone 4 is "sweet." The much-touted “Retina Display” screen is gorgeous. “There has never been a more detailed, clear, or viewable screen on any mobile device,” raves Engadget. Shots from the 5-megapixel camera “look stunning,” and FaceTime video calling is “actually a teensy bit amazing.” But there’s one big glaring problem, notes Xeni Jardin of Boing Boing: “AT&T still sucks, and the best engineering out of Cupertino won't change that.” There are still plenty of dropped calls, to say nothing of the data plan issues. But bottom line: “Would I buy it? Yes.”