Apple's often imitated but never bettered ultra-portable laptop puts in a strong, though not faultless, performance with this mid-2013 release, the sixth-generation of the MacBook Air.
It offers significant improvements in its solid state storage speed, graphical power, battery life and wireless capabilities, but the processor's clock speeds actually take a backward step. But as we'll see, for most real-world applications, the MacBook Air 2013 matches or out-performs its predecessor.

Like most recent MacBook Air refreshes, the mid-2013 update brings us four new models; two with 11-inch screens and two with 13-inch displays. All use Haswell 1.3GHz Intel Core i5 dual-core processors, replete with Intel HD Graphics 5000, the latest version of Intel's integrated graphics chipset. They also all run the OS X 10.8 Mountain Lion operating system, although this will change to OS X Mavericks when available.
The cheaper model in each of the two screen sizes has 128GB of solid state storage, the more expensive version has 256GB, and all offer 4GB of RAM.
The version on test here is the top-of-the-range 256GB 13-inch MacBook Air, which costs £1,129 / US$1,299 / AU$1,449. The lower specced 128GB 13-inch model is £949 / US$1,099 / AU$1,249.
If your budget won't stretch that far - or if you just want a smaller model - the 11-inch MacBook Airs are priced at £849 / US$999 / AU$1,099 for the 128GB version and £1,029 / US$1,199 / AU$1,349 for 256GB of storage.
While the quality of the MacBook Air isn't in question, not everyone is prepared to pay so much for a light, carry-around notebook. For those on a budget, Chromebooks offer good value for money, as long as they meet your needs.

Eschewing OS X, Windows and Linux for Chrome OS, these run web-based applications and can be bought very cheaply. For example, the Samsung Chromebook cost just £230 / US$330 / AU$320 at launch.
More expensive Chrome-powered notebooks are available too, though. Google's own Chromebook Pixel is a gorgeous high-end notebook costing £1,050 / US$1,300, which is more than either of the two 11-inch MacBook Airs in the mid-2013 refresh, but it proves cloud computers can be as stylish and desirable as an Apple notebook.
If you want a Windows 8 ultra-portable notebook, the Samsung Series 9 NP900X3D has an Intel Core i5 processor, a 13-inch screen and 128GB of flash storage like this MacBook Air. If you prefer Windows to OS X, the Lenovo ThinkPad X1 Carbon Touch is one of the thinnest and lightest Windows 8 netbooks on the market, and a very credible alternative to the MacBook Air.

People who want a Mac but need a lot of processing power, such as video editors, gamers and graphic artists, might be better off with a MacBook Pro or an iMac. But the MacBook Air is fine for everyday computing, and perfect for business travellers and regular commuters.

We've previously tested Haswell chips in a few laptops and been impressed by both the performance and battery life gains (to be realistic, the latter is much more important for consumers). If you add Haswell to Apple's already-stellar battery life reputation, you get a system, in the 13-inch Air, that Apple claims will run for up to 12 hours, and in our tests (spoiler alert) ran even longer.

Sarah Tew/CNET

Having a Haswell-generation CPU also gives you Intel's improved HD5000 graphics, which promises improved game performance over last year's HD4000 graphics (itself an improvement over the preceding HD3000, and so on). It's still not anything like having a discrete GPU, as in the 15-inch Retina Pro , but with game services such as Steam and EA's Origin now being Mac-compatible, it may make some small inroads for OS X gaming.
Also new is 802.11ac Wi-Fi , a new standard that will eventually be found in wireless routers, as well as Apple's new AirPort Extreme and AirPort Time Capsule hardware. If you have an 802.11n router, which is a much more likely scenario, this may not help you, but it's a nice piece of future-proofing. Apple also says the solid-state-drive storage included in the Air laptops is now faster, although I think bumping the base $999 11-inch model up to a full 128GB of SSD storage (from the paltry 64GB previously sold at that same price) is a much more important development.

Sarah Tew/CNET

It's easy to say that this new version of the 13-inch MacBook Air is a modest step forward, with no physical changes to the exterior, and still no higher-res display, touch screen, or HDMI port. The battery life is a very big deal, however, and when you couple that with a $100 price cut on the base model, down to $1,099, the 13-inch MacBook Air is, despite not being the newest design on the block, still one of the most universally useful laptops you can buy.

Design and features
The MacBook Air keeps the same external look as the previous couple of generations, a look that still rivals the newest ultrabooks, although some new systems, such as Sony's Vaio Pro line , are getting thinner and lighter without sacrificing much in the way of productivity.
Both the 11-inch and 13-inch versions of the MacBook Air still have the same thickness, ranging from 0.11-inch to 0.68-inch. Spread over the larger footprint of the 13-inch chassis, the 13-inch version still feels satisfyingly thin.

The Vaio Pro 13 next to the 13-inch MacBook Air. Sarah Tew/CNET

As with the previous version, the rigid aluminum construction makes the Air feel sturdy enough to just throw it in a bag and carry along with you without a protective case or sleeve, and it's interesting to contrast the aluminum unibody construction here with the lighter carbon fiber in the aforementioned Vaio Pro. I'd still trust the Air and its unyielding lid more in a throw-in-your-luggage field test.

The backlit keyboard and trackpad are the same as on the previous models, and the trackpad especially remains the standard by which all others are judged. Many other laptop makers have moved to larger clickpad-style touch pads, but we have yet to find a touch pad that comes close to this for multitouch gestures. The pad is again hinged at the top, allowing the entire pad to click down, and we strongly suggest going into the Preferences menu and turning on all of the tapping options for further ease of use.

It will be interesting to see how Apple's user interfaces develop in the face of both Windows 8, which tries (not terribly successfully) to reinvent the entire concept of working with a computer OS, and the upcoming OS X Mavericks update . For now, flicking around with three-and-four-finger gestures on the MacBook trackpad remains the most seamless way to swap between windows and applications, at least in my experience.
Unlike on the 11-inch MacBook Air, the 13-inch screen is still not a 16:9 display. The screen area also lacks the edge-to-edge glass over a black bezel found in the MacBook Pro; instead the screen is, as in previous years, surrounded by a thick silver bezel.
On the positive side, the native resolution of the display is 1,440x900 pixels, which is better than the 1,366x768 you find in many 13-inch laptops, although even midpriced models are quickly switching over to 1,600x900 or even 1,920x1,080. Of course the Retina Pro models, along with a handful of laptops from Toshiba, HP, and Dell, are experimenting with even-higher-than-HD resolutions.
While the Air screen isn't flat matte, it's also not terribly reflective, which is a step up from the "mirror image" effect you get on some laptop screens.

	Apple MacBook Air (13-inch, June 2013)
Video	DisplayPort/Thunderbolt
Audio	Stereo speakers, headphone jack
Data	2 USB 3.0, SD card reader
Networking	802.11ac Wi-Fi, Bluetooth
Optical drive	None

Connections, performance, and battery
The ports and connections remain unchanged on this version of the MacBook Air. That gives you two USB 3.0 ports and a Thunderbolt port to play with, with the latter used for both external accessory and video connectivity. The faster 802.11ac Wi-Fi will play nice with Apple's own upcoming new AirPort Extreme and AirPort Time Capsule hardware, but I suspect you're still working off an 802.11n router. There's more on what 802.11ac means for you here .

Sarah Tew/CNET

The base configuration for the 13-inch Air now costs $1,099, versus $1,199 previously. Most of the system is unchanged, with the main difference being the new Haswell-generation Intel processor and platform. Interestingly, last year's base model CPU was a 1.8GHz dual-core Intel Core i5, while the newer Haswell version is a 1.3GHz Intel Core i5-4250U. The step-up $1,299 configuration keeps the same CPU as the $1,099 one, but doubles the SSD to 256GB. 
Benchmarks
Xbench: 357.50
Cinebench 10 Single core: 4242
Cinebench 10 Multi-core: 8636
iTunes encoding (USB SuperDrive): 452 seconds
Movie encoding (iMovie): 242.6 seconds
Doom 3: 68.9fps
Call of Duty 4: 67.8fps
Battery: 9 hours
Novabench, Total: 589
Novabench, Graphics: 44
Although the processors have a slower clock speed than the previous generation, across-the-board performance improvements mostly make up the difference.
The faster graphics enjoyed by the Haswell processors meant that in our Call of Duty 4 test, the 2013 13-inch MacBook Air ran the game at 67.8 frames per second, compared to 59.5fps for the 13-inch, 1.8GHz dual core Intel Core i5 model from 2012.

Battery life is where the new MacBook Air (both the 11-inch and 13-inch versions) really stands out. The previous-generation 13-inch Air ran for 7 hours and 27 minutes in our video playback battery drain test. The 2013 version blows that out of the water, with an astonishing 14 hours and 25 minutes on the same test. That's better than Apple's estimate of 12 hours, and one of the only times our tests have indicated longer battery life than a manufacturer's claims.
Now, before we get too excited, there are a few caveats for that number. Much of the credit must got to Intel's fourth-generation Core i-series platform, which was pitched as being incredibly power-efficient. Our early tests confirm this, with the new 13-inch Sony Vaio Pro 13 running for nearly 9 hours. And, while this is a much better score than last year's Air, the CPU itself runs at a lower clock speed, and the new Intel chips are especially optimized for video playback, which is the heart of our battery test. Using Wi-Fi and Bluetooth heavily or playing 3D games would cause that number to drop.
But even keeping those factors in mind, Apple's typically stellar battery achievements and Intel's new Haswell chips have combined to make this a truly all-day laptop.

Source
Engadget Apple MacBook Air 13-inch Reviews (Critic Reviews 8.8/10, User Reviews 9.0/10)
Techradar Apple MacBook Air 13-inch Reviews (Design 4/5, Features 4/5, Perfomance 4/5, Usability 5/5, Value 3/5)
PC Mag Apple MacBook Air 13-inch Reviews (4.5/5)
CNET Apple MacBook Air 13-inch Reviews (CNET Editor's Rating 4/5, Average User Rating 4.5/5)

The Good New Intel fourth-gen CPUs help the updated MacBook Air achieve amazing battery life. The multitouch trackpad is still the industry's best, and even better, the 13-inch MacBook Air now starts at $100 less than the previous model.

The Bad Newer features such as touch screens and higher-resolution displays are still missing. The ultrabook competition is catching up, in terms of design.

The Bottom Line Apple keeps the latest MacBook Air updates on the inside, but greatly improved battery life and a lower starting price make up for a lack of flashy design changes.

Official Website

Where to Buy
$1,099.00 - $1,299.00 Apple Store 13-inch MacBook Air
$1,099.99 Ebay Apple MacBook Air 13.3" 4GB RAM, Core i5, 1.3 GHz, 128 SSD (June 2013)*free shipping
$1,048.99 Amazon Apple MacBook Air MD760LL/A 13.3-Inch Laptop (NEWEST VERSION)*free shipping
$1,259.00 Amazon Apple MacBook Air MD761LL/A 13.3-Inch Laptop (NEWEST VERSION)*free shipping