Following all the hype and hysteria we have come to expect with the launch of Apple products, the Apple iPhone 4S is finally about to land, leaving a trail of smartphones in its wake. However, don't go writing off its predecessor, the iPhone 4, just yet.

Despite being one of the most remarkable phones of the past five years, the Apple iPhone 4 landed with a troubling signal loss issue for anyone holding the iPhone 4 “incorrectly” – who knew prior to June 24 2010 that there was a “correct” way to hold mobiles?

Our findings so far are that when you hold the iPhone 4 with your hand covering the bottom left corner, there is a loss of signal. However, we have not found that this has caused us to drop calls or lose data connections when out and about actually using the handset.

Whether this is because we’re subconsciously moving our hands to avoid the issue developing is hard to say. That aside, there is no denying that the Apple iPhone 4 is a stunning piece of tech.

iPhone 4: Size and build

The handset is 24 per cent slimmer than the 3GS at just 9.3mm thick, beautifully compact and elegantly designed with a stainless steel band separating the handset’s scratch-resistant glass covered front and back.

It’s this steel band, which is also the aerial, which seems to be causing the problems. Presumably it’s something to do with contact between the metal band and human skin causing conductivity issues as putting a casing on the iPhone seems to alleviate the problem.

Bizarre reception flaws aside, the iPhone 4 is a great showcase for Apple’s technological and design prowess. The combination of the new Apple iOS 4 operating system and a noticeably faster processor than the iPhone 3GS make using it a very smooth and enjoyable experience.

iPhone 4: Screen

The new 3.5-inch Retina Display is another big improvement over the 3GS – and all other mobile devices for that matter. With an 800:1 contrast ratio and 960x640p resolution – according to Apple, that’s more than the human eye can process at that size of screen – the Retina Display sets a new benchmark for mobile screens.

The Retina Display is a joy to use indoors and at most outdoor light levels, although it becomes reflective and difficult to admire when in direct, bright sunlight.

Although adding a gratifying pop to images and videos, older applications and their icons can also appear dated and grainy on the new high-res screen – app developers will have to improve their wares for the iPhone 4. They’ll also have to adapt their apps to allow them to be part of the newly added multi-tasking in iOS 4.

iPhone 4: Performance

Bringing the iPhone 4 to life is the same sprightly Apple A4 processor found in the iPad. You’d think that packing this hefty workhorse under the bonnet would drain the battery, but the new iPhone’s battery life is not noticeably diminished from the 3GS, and Apple claims it actually lasts longer.

As noted, iOS 4 brings multitasking to the new Apple handset. This feature is reliant on the compatibility of apps, but this should cease to be an issue pretty sharpish: iPhone purchasers are not likely to look kindly on app developers who don’t update to support multitasking.

iOS 4 is no one trick pony. The ability to create folders for your apps is another very welcome addition, as is the option to set homescreen images, scrapping the any-colour-as-long-as-it’s-black background of previous models.

iBooks makes the jump from Apple iPad 2 to iPhone with the arrival of iOS 4 and thanks to the iPhone 4’s Retina Display offers up text of impeccable clarity. Crystal-clear fonts similarly enhance web browsing, email and all other text-based functionality. The addition of iBooks will no doubt be a further cause to the iPhone’s success with the commuter market

iPhone 4: Camera

Following repeated cries from consumers, the iPhone 4 now offers flash. No, not the Adobe version for viewing web video – that’s just not gonna happen, so get used to it – but a scorchingly bright LED flash to accompany the improved camera.

Stills are not suddenly of compact camera quality, but they are undeniably better, and bigger at five megapixels. Video is much improved, with 720p HD video offering pristine and sharp detail on the Retina Display.

However, some detail seems to be lost when compressing for direct uploading to YouTube. In-camera editing is also straightforward, and you can add the iMovie app (£2.99) if you want more sophisticated editing of your clips.

In addition to the main, rear camera there’s a second, front-facing one. This offers decent picture quality, but it’s there for more than just vanity’s sake. Apple, you see, is attempting to transform video calling from its current status as the forgotten starlet of the tech world into a must-have feature.

To this end, it’s included the Skype-style Face Time app. Given that this works only over Wi-Fi and only between one iPhone 4 and another, we can’t see it reviving video calling’s fortunes, somehow, but it does work nicely enough, with much better video quality than on earlier mobile systems

iPhone 4: Verdict

The Apple iPhone 4 is another classic slice of Apple. In just 12 months Steve Jobs and his band have again redefined mobile handsets.

From the simply beautiful Retina Display to the addition of HD video, and from the idiot-proof UI to the attempted reinvention of video calling, the Apple iPhone 4 is a majestic piece of kit that will no doubt steal hearts. As long as that signal-loss issue doesn’t prove to be a killer, anyway…

Apple iPhone 4 release date: Available now

Apple iPhone 4 price: From £319