When Apple unveiled the iPhone 5, the reaction was a bit muted: where previous phones were massive leaps forward, the iPhone 5 was a bit longer and a lot easier to scratch.

So what can we expect from the next iPhone, the iPhone 6 or 5S? Let's see what the crystal balls are saying.

One thing is for sure, with the release of such super handsets as the Samsung Galaxy S4, Sony Xperia Z and HTC One, the next iPhone will have to seriously up its game.

iPhone 6 and the iPhone 5S are two different phones

The rumour mill doesn't seem too sure whether the next iPhone is going to be the iPhone 5S or the iPhone 6. Given the iPhone's history - from the 3G onwards, there's always been a half-step S model before the next numbered iPhone - we'd bet on an iPhone 5S first and an iPhone 6 a few months later.

iPhone 6 release date

Some pundits predict a summer release for the iPhone 6, while Money Morning reckons that the iPhone 5's lack of NFC and Jumbotron display is because Apple's got a proper iPhone ready for a springtime release.

It's quite likely that Apple is moving to a two-phones-per-year upgrade cycle, but we'd bet on a springtime 5S model and a bigger, iPhone 6, update in the Autumn, probably September.

Even Digitimes reckons a springtime iPhone 6 is unlikely: it's predicting a summertime reveal for Apple's next generation phones, which again fits with a WWDC unveiling.

iPhone 6 cases

Multiple rumours say Apple's working on plastic cases for its next iPhone, mixing plastic and metal in such a way that "the internal metal parts [are] able to be seen from outside through special design."

It's unclear whether such cases would be for the iPhone 5S or iPhone 6, or if Apple is simply considering making cheaper iPhone 4s to sell when the iPhone 3GS reaches the end of its life.

Speaking in March 2013, a KGI analyst said it believed Apple would turn to manufacturer Pegatron to make up to 75 per cent of low cost iPhone products.

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That's what iDownloadblog reckons, quoting Jefferies analyst Peter Misek: it'll have a better battery too, he says.

The iPhone 6 will run iOS 7 and the iPhone 5S probably won't

Developers are seeing new iPhone model identifiers in their server logs: the device identifies itself as the iPhone 6,1 (the iPhone 5 is 5,1 or 5,2) running iOS 7, and its IP address is an Apple one. If the two-phones strategy is true, we'd expect Apple to unveil the next major revision of iOS at its WWDC conference in June, with it shipping on the iPhone 6 a few months later.

iPhone 6 storage

We've already seen a 128GB iPad, so why not a 128GB iPhone 6? Yes, it'll cost a fortune, but high-spending early adopters love this stuff.

It may not have a home button

According to Business Insider, of the many iPhone 6 prototypes Apple has made, one has a giant Retina+ IGZO display and a "new form factor with no home button. Gesture control is also possibly included".

iPhone 6 screen size

Take this one with a pinch of salt, because China Times isn't always right: it reckons the codename iPhone Math, which may be a mistranslation of iPhone+, will have a 4.8-inch display. The same report suggests that Apple will release multiple handsets throughout the year over and above the iPhone 5S and 6, which seems a bit far-fetched to us.

The screen may be magic

Patents show that Apple has been thinking about magical morphing technology that can hide sensors and even cameras. Will it make it into the iPhone 6? Probably not.

iPhone 6 processor

Not a huge surprise, this one: the current processor is a dual-core A6, and the next one will be a quad-core A7. The big sell here is more power with better efficiency, which should help battery life.

Expect to see it in the 2013 iPad first, and expect to see an improved A6 processor, the A6X, in the iPhone 5S.

iPhone 6 camera

Apple's bought camera sensors from Sony before, and this year we're going to see a new, 13-megapixel sensor that takes up less room without compromising image quality.

The new iPhone will have better 4G LTE

On its UK launch, just one UK network had 4G LTE: Everything Everywhere, which currently offers 4G on the 1800MHz band. In 2013, all the other big names will be coming on board, offering 4G in other frequency bands. International iPhones already work across different 4G bands to the UK, so you can expect the UK iPhone 6 (and possibly the iPhone 5S) to be more promiscuous than the iPhone 5.

The Wi-Fi may be 802.11ac

Apple likes to lead Wi-Fi standards adoption - its Airport really helped make Wi-Fi mainstream - and there's a good chance we'll see ultra-fast 802.11ac Wi-Fi in Apple kit this year. It's faster than Lighting, and not very frightening.

It may get wireless charging

Wireless charging still isn't mainstream. Could Apple help give it a push? CP Tech reports that Apple has filed a patent for efficient wireless charging, but then again Apple has filed patents for pretty much anything imaginable.

The tasty bit of this particular patent is that Apple's tech wouldn't just charge one device, but multiple ones.

With a cutting-edge camera, a super-slim design and the ability to withstand life's knocks and bumps (and Android Jelly Bean to boot) the Xperia Z is a phone that's got us fired up about Sony Mobile again.

Earlier handsets such as the Sony Xperia S and Sony Xperia T were extremely promising from a brand striking out on its own - but it's with the Xperia Z that Sony is really banking on making a cataclysmic dent in the makeup of the smartphone market.

If you don't believe us, just look at its marketing hype - Valentine's Day saw ads on several, consecutive pages of major newspapers in the UK and you can't pass a billboard without seeing it in glorious Technicolor, accompanied by a strong statement that Sony has "reinvented the phone."

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The Android Jelly Bean-toting (albeit only 4.1) Sony Xperia Z comes with some of the best specs on the market - and it's one of the most eagerly awaited handsets of recent months. Launching before the HTC One orSamsung Galaxy S4, Sony is clearly hoping to steal an early march on its competitors.

And the early signs it will do so are promising: a quad-core 1.5GHz Snaprdragon Krait processor, 13MP camera, 16GB storage (expandable, woohoo!), 2GB RAM, water and dust-resistant, 1080p HD screen with Bravia Engine, LTE, to name a few. You couldn't make this stuff up - this is the company that had a part in the Satio, after all.

As soon as we took our review unit out of the box, we were mesmerised. This feels and looks like a premium, high quality product. Sony is one of the few manufacturers that can take what is, effectively, a plain black square and make it into something beautiful. Manufactured from piano black, high gloss glass both front and black, it could have come from the same stable as the Google Nexus 4.

Though maybe we are overestimating it, viewing the Sony Xperia Z through geek-tinted goggles - because while we were blown away, others came out with the line that Sony will be hoping doesn't cross too many punters' lips: "looks like every other smartphone out there though, doesn't it?"

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One thing the Sony Xperia Z certainly does have in common with every other smartphone out there is the fact that it is a pure magnet for fingerprints. You'll struggle to keep it clean all day long without either surgical gloves or a can of Mr Sheen in your bag.

As is fast becoming the norm, you can expect to pick the Sony Xperia Z up in white too. On top of that, O2 in the UK is exclusively offering a purple variant.

If you're coming from something like a Samsung Galaxy S3, it'll feel similar, if a little larger, in terms of size: the Sony Xperia Z rocks in at 139 x 71 x 7.9mm/5.47 x 2.79 x 0.31 inches, so there's little room for anything else in your hands.

Coming from something smaller like, say, an iPhone 5, you'll certainly notice the difference. But it's amazing how quickly you'll adapt.

At 146g/5.15oz, it's by no means the lightest handset out there - but the Sony Xperia Z exudes a heftiness that belies a quality device. It's on a par with Apple's offering when it comes to the thickness.

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The ports are spread out with the headphone jack up top, the SIM slot and volume rocker on the right - either side of a silver standby button - while both the microSD and charging ports are on the left, alongside contacts for accessories. A watertight port covers each.

The front of the Sony Xperia Z is minimalist - showing off only a Sony logo and front-facing camera. The rear is a little busier, with various tech info printed on it, plus the Sony Xperia logo, an NFC badge, camera light and the all-important lens. That back is stuck fast - as is becoming the custom, you'll have no luck if you want to remove the battery.

Turn it on, and you're not disappointed. Coming from the blackness, the 5-inch screen springs into life. Whether or not you'll like it is down to personal choice.

Some who've used the Sony Xperia Z describe the screen as a disappointment because Sony has gone for TFT - albeit with 1080 x 1920 pixels, giving a pixel density of 441ppi, which would explain why it looks a bit washed out. If you've come from a Super AMOLED screen you'll definitely feel the difference.

We're still fans - this is a razor sharp display from one of the world's premier screen manufacturers, although it doesn't have the wow factor of the HTC One's Super LCD 3 screen.

The only thing that lets it down is viewing angles - if you look at the Sony Xperia Z's screen, dead on, it's sharp enough. If you look at it from the side, it has a strange ability to look incredibly washed out. It's no huge problem - but it does mean the impressiveness of the screen is diminished compared to the likes of the Samsung Galaxy S4 or the HTC One.

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One of the selling points of the Sony Xperia Z is that it is also water resistant. There's something slightly unnerving about taking a £529 phone and dropping it in the sink - but that's exactly what we did. And it worked absolutely fine.

Clearly, you'll need to make sure the ports are covered using those watertight protectors, that much goes without saying.

And here's some more good news: the price of the Sony Xperia Z is dropping quite quickly, already making it cheaper than the likes of the HTC One and could soon sneak under the £30 contract mark for a half-decent whack of minutes.

While it's actually the same price as the comparable SIM-free 16GB iPhone 5, the cost is now closing in on the iPhone 4S on PAYG, so we can't help but feel the Xperia Z is finding its natural pricing level.

This could be a major set back for BlackBerry 10 as the brand spanking new operating system hasn't passed government security tests - branding it "not secure enough for essential work".

The UK's Communications-Electronics Security Group (CESG) cleared the older BlackBerry 7.1 system in December last year, reports the Guardian, marking it safe for use up to the "Restricted" classification - which is two levels below "Top Secret".

With the launch of BB 10 the corporate market was seen as its main entry point back into the mobile game; however this latest blow means the Canadian firm will struggle to get the BlackBerry Z10 into hands of people in high places.

It's not just the BlackBerry 10 platform which is at fault, with the BlackBerry Balance software - which allows users to manage personal and work accounts separately - also failing to make the grade.

If at first you don't succeed

The Government is one of BlackBerry's biggest customers in the UK, alongside the NHS, and it would be a massive blow for the firm if it were to lose such a lucrative partnership.

It's not giving up though and you can expect BlackBerry to tweak its BB10 software and then resubmit to CESG to get that coveted clearance rating.

In a statement BlackBerry said: "We are continuing to work closely with CESG on the approval of BlackBerry 10 and we're confident that BlackBerry 10 will only strengthen our position as the mobile solution of choice for the UK government."