Taken from : //www.macnn.com/reviews/iphone-3gs.html

iPhone 3GS

June 27th, 2009
An evolutionary but very welcome update to the iPhone formula.

Apple enthusiasts have almost been lulled into a certain degree of complacency with iPhone releases in the past two years: each one has been accompanied by a major hardware change along with whatever software changes may have been promised. The iPhone 3GS marks the first time Apple has had a subtler upgrade in store. But with a faster processor and graphics, a digital compass and voice control, is it enough to persuade first- or second-generation iPhone buyers to invest? We'll find out in a special review that focuses on what's new.

design changes

Quite simply, there are very few practical changes to the outside of the iPhone 3GS. In fact, if not for replacing the matte lettering on the back with chrome-effect material or the tell-tale 32GB of storage (as with our model), it's virtually impossible to tell the two apart. This isn't necessarily a flaw, as it's reasonably easy to hold and slim. We do wish Apple chose a material with better grip and scuff resistance for the back, however, such as the Teflon that HTC uses for the Hero. Without a rubber or silicone case, there's always a sense that the phone may slip out of your hand if you're too careless.

One change is undetectable but very valuable: an oleophobic (oil-resistant) display surface. The change doesn't affect the feel of the touchscreen but has a tangible impact on how it looks. It doesn't eliminate smudges entirely, but it does make them easy to remove and prevents spots from clinging to the screen if it hasn't been scrubbed with a damp, lint-free cloth. In several days of use, the iPhone's display is still looking as good as it did when brand new without extensive attention, which couldn't be said for the iPhone 3G.

speed: the iPhone's centerpiece

Everyone who has had extended time with any previous iPhone has noticed that the near-instantaneous experience shown in Apple's TV ads have been at odds with reality. Apps take longer to load, websites render slowly even on fast connections and 3D games sometimes bog down.

Virtually all of that changes with the 3GS. It's made the leap to a much newer processor era (the ARM Cortex A8), and the difference is dramatic: most apps are ready to use within one to two seconds and transitions are often near-immediate; games that would take an interminable time to load now start up with the speed they might in a desktop version. On Wi-Fi, where connection speed isn't a bottleneck, websites rarely take more than several seconds to completely render where they may have taken 15-20 seconds to draw before. Some of this is owing to the much faster JavaScript engine inherent in iPhone 3.0, but even then the 3GS is noticeably faster with the same content. We've seen forums and similarly graphics-light, code-heavy sites load in as little as two seconds.

We've also noticed higher frame rates in games, even in not particularly stressful titles such as Zen Bound. Some of this is owed to the processor, but it's here that a graphics update to the new PowerVR SGX (believed to be an SGX 535) can probably be given credit. While the new video hardware's help is generally less evident than the new CPU, it holds a lot of potential for the future: if and when game developers opt to write for the new hardware, they'll have the option of adding more visual detail as well as visual effects that aren't possible at any speed on prior iPhones. If you consider the iPhone a frequent if not only gaming platform, consider trading up soon.

Buying the iPhone 3GS for its faster 3G speeds would be a mistake, however. While it's true that the theoretical peak speed has doubled from 3.6Mbps to 7.2Mbps, real-world speeds don't change. We had the luxury of testing the new iPhone on a 7.2Mbps network with Rogers, and while data did load faster than on an iPhone 3G with the same 3.0 software, we'd attribute that gap more to the processor than the actual access speeds. It likely won't be until 2010, when the iPhone has a chance of supporting next-generation 21Mbps 3G networks, that the difference away from Wi-Fi should be noticeable.

new camera and video

Outside of the CPU and GPU, the 3GS benefits the most from an upgraded camera sensor. The 3.2-megapixel resolution is still well below that of some challengers, which are now often at 5 megapixels or higher, but through our testing it's clear that the new iPhone's camera is almost uniformly better than its predecessor and may be more useful than those of challengers. Without including other changes that affect output, images appear to be cleaner and less prone to noise in low light. It's still a bad idea to take photos in a dark nightclub or other areas, as Apple still doesn't include a flash, but it's much better than the at times all-too-grainy images of previous iPhone models when taken in less than ideal conditions. Colors are vibrant without being overdone and images don't seem to suffer the "smear" symptomatic of a poor-quality plastic lens.

The new handset is much more accomplished than that thanks to the addition of autofocusing. This has existed on many other phones but is particularly advanced on the iPhone 3GS through the touchscreen. Touching on a particular area of the screen now not only puts objects in that area into clearer relief but also adjusts the exposure and other settings based on that point. Effectively, it's spot metering without needing an SLR or an advanced point-and-shoot. Adding this one feature instantly transforms the quality of most iPhone images; it's now possible to get shots with a mild amount of bokeh (shallow depth of field) as well as to shoot macro images. You still won't replace a dedicated camera, but the change is enough that iPhone owners can be truly creative without resorting to accessories or being fortunate with their choices of subject.

Video recording, too, is new and is surprisingly well-executed for a first attempt even compared to companies that have had years of practice. Apple's recording scales up to VGA (640x480) at a TV-speed 30 frames per second and appears to maintain a fairly high bitrate that preserves much of the audio and visual quality. There are still signs it's not a camcorder: there are slight signs of the "wobble" inherent to a cellphone-sized sensor and lens, for example, and it doesn't handle transitions to bright or dark lighting well. Similarly, autofocusing also doesn't seem to be as dynamic as in still shots. Even so, it's visibly better than many modern phones with video recording. For comparison, the HTC Magic we recently tested not only records at a quarter the resolution but at a reduced frame rate as well as with more visible compression and optical artifacts.

The post-shoot software is enjoyable to use as well, albeit not without its limits. Editing a clip is as simple as dragging starting and ending points and tapping "trim." Uploading is also extremely easy and supports renaming, tagging and other common features for both MobileMe and YouTube. We had our test video online quickly and thankfully without stress. Our chief complaints center only on the complexity of edits: we don't expect iMovie, but it's not possible to keep multiple segments of a given clip or to recover footage that's been cut out. Still, we'll take the quality and rapidity of producing video, and we can see mobile-generated videos on YouTube exploding in popularity due to what Apple's accomplished at this early stage.

the compass

While it positions itself as a technology leader and certainly is one in mobile chips, the iPhone 3GS is actually late to the field in adding a digital compass, also known as a magnetometer. It now lets the iPhone indicate its direction without first needing to move, as the earlier iPhone did for those few apps that can recognize it.

For now, Google Maps benefits the most from the feature. Tapping the location button a second time now orients the map view relative to the iPhone's facing. This can be particularly useful for confusing streets or just for those without a good sense of position; we didn't find it critical, but it was certainly appreciated.

The same can't be said for the self-explanatory Compass app. Simply put, it strikes as loaded on to the 3GS solely to advertise the new hardware. There are a few niche uses such as hiking, but for the most part it comes across as a novelty.

As with the graphics technology, though, the compass will be useful in the future. Turn-by-turn GPS will benefit by providing more accurate guidance. We could moreover see Google Maps' Street View using it in the future should Apple choose to link the compass to the user's point of view, much as Android phones already do. No matter what happens, Apple has at least put in place a useful addition with groundwork for the future.

voice control

Again showing Apple trailing behind competitors even as it leads them in some areas, voice commands are also new to the iPhone 3GS despite them existing on BlackBerries and other phones for years. They're certainly welcome all the same, and they can be potential time- or even life-savers by taking users' attention off of the phone and towards where they're going.

How well it works depends on the task at and and the noise conditions in the area. We found it works best for voice calls indoors. It's intelligent enough to recognize most names, including some partial names, and can narrow calling down to a specific contact without a second prompt. Saying "call John Smith home" will skip directly to that person's number. It's especially useful with the wired headset, though we'd warn buyers that it doesn't (yet) support Bluetooth headsets or speakerphones; as such, it's still not as good as some rival devices.

Music isn't as reliable as we'd like. While it can recognize certain artists and songs immediately, the voice recognition is prone to identifying the wrong artist or track even when the name should be simple. There are advanced music controls that don't exist on many other phones, such as invoking a Genius playlist or shuffling tracks, but these too at times don't register properly. Until Apple can improve the detection algorithm -- if that's the issue -- or otherwise improve the reliability of its voice system, we'd still recommend using physical headset controls (which now have volume buttons) and the touchscreen to steer most music.

battery life and call quality

Gauging battery life on the iPhone 3GS is difficult because of the added performance and feature set, but we've noticed that the iPhone seems to drain slightly faster than the iPhone 3G in spite of Apple's claims to the contrary. Some of this owes to where the battery is most likely to run dry. 3G calls and data, games, GPS and video recording are all going to consume battery life much more quickly than Wi-Fi browsing or calling on GSM, and the speed may actually work against power users by encouraging them to do more in a short space of time. Those who intend to record movies often or know they'll spend long periods of time away from Wi-Fi should still consider an external battery pack, although for mild to moderate use the 3GS should last for most or all of a typical work day.

Call quality is virtually identical -- that is to say, good. We had little trouble in understanding either end of a conversation, and the external speaker is loud if set at higher volume levels. It's not flawless as a small amount of detail is lost, but we'd place the newer iPhone in the upper range of quality compared to other phones we've tested, smartphone or otherwise.

a note on iPhone 3.0

We've already discussed features of the new iPhone 3.0 software that aren't specific to the 3GS, so those who want to explore device-wide search, voice memos and other key additions are encouraged to read our iPhone OS 3.0 test to see how they fare. It would be easy to summarize many of these as helpful, but not game-changing, additions to the core iPhone experience. They both take care of long-standing feature omissions as well as performance issues for older hardware.

On the 3GS, these changes are amplified: searches run faster, there's more storage for voice memos, and jumping between apps to copy and paste text is that much quicker. Dedicated navigation apps will undoubtedly reap some reward from mating the compass to 3.0's hooks for turn-by-turn directions, too. It's evident iPhone 3.0 was made for the new device, even if it provides a benefit to legacy hardware.

wrapping up and buying advice

As an evolutionary upgrade, the iPhone 3GS still won't please some without a fundamental change in its technology, if it can please them at all. The Palm Pre's multitasking isn't something that can be replicated without a major overhaul of the iPhone's user interface. Likewise, Apple's aversion to a hardware keyboard will deter those who are convinced they need physical feel to type well (they don't). We can't give it a perfect rating as a result, and we don't believe there will truly be such a thing as a perfect phone.

Certain features also appear to be rough or underused. Voice control is the most obvious example, but the compass needs more than just a single Google Maps feature and a simple stand-alone app to be useful.

But when seen in its entirety, the iPhone 3GS is still a very capable phone and a decided step forward for Apple. There's no one feature that will necessarily tip the balance; rather, it's the aggregation of a series of noticeable improvements that add up to a convincing package. If there's more than one feature that seems worth having, particularly the better camera or the improved speed, it can well be worth the upgrade -- at least, if your carrier will give you a full subsidy on the otherwise high price. Some carriers won't allow full upgrade discounts due to the already high discounts they're forced to apply, and if you're one of those who bought an iPhone 3G in 2008 or early 2009, it's harder to justify upgrading so soon unless you can't live without certain new features that iPhone 3.0 doesn't already supply.

Perhaps the best compliment that can be given to the 3GS is that it eliminates many of the reasons for picking a competitor's phone instead. Autofocus and video recording aren't only in effect; they're done well. Its voice control is at least on par with other devices and is at times better, even if its music control isn't where we'd like. And once apps are written to exploit the compass and faster performance, the new iPhone may simply be in another league. It could be prudent for those who just bought into the iPhone last year to wait, but for original iPhone owners or those switching to the platform for the first time, the 3GS is most likely the best upgrade Apple could have hoped to deliver in the space of a single year.

- Much improved performance; very fast.

- Significantly better camera; simple but capable video capture.

- Voice control on par or better than with rivals, if overdue.

- Oil-resistant screen.

- Navigation improved through the compass.

- Still no multitasking in this generation.

- Battery seems to drain slightly faster in practice.

- Voice control is inaccurate with music, doesn't support Bluetooth.