If you were a logical iPhone upgrader, you would be getting ready to preorder the iPhone 6. It's a lovely device and one that many will opt for when it comes to buying a new phone on 19 September. The chances are, if you are reading this, you aren't the kind of person to make that logical step.

In a surprise announcement, and breaking with tradition, Apple has launched the iPhone 6 Plus, a device that comes with a 5.5-inch display, optical image stabilisation, and a few other tricks over the regular iPhone 6 announced alongside.

We've been playing with the new iPhone 6 Plus to see whether bigger is better.

It's big, like really big, but surprisingly not that thick. It will make a dent in your pocket but not in the way that you are expecting. We slipped it into a pair of regular jeans and the phone hardly made a dent. If you're of smaller stature, or have shallow pockets, like on a pair of shorts, then you might have a problem however, but the slimness is noticeable over the current iPhone 5S. 

Next to the iPhone 5S it's decidedly massive, but gosh that screen. With its high-resolution "Retina HD" 1920 x 1080 pixels screen the is crisp. Watching movies is amazing, and new features in iOS 8 will allow you to make more of that screen real estate. It will also please those who have got lots of work to do. When iOS 7 launched we said that it was designed for a big screen and this is the realisation of that. The colours are vibrant and the viewing angles are excellent.

We aren't entirely sure why Apple made the decision to push the boat out on the resolution here, but not on the iPhone 6, but we aren't complaining. Watch video footage that we had recorded at the event looked good watching it back on that screen. 

Like the iPhone 6, the iPhone 6 Plus features the same design with a curved front screen to reduce the edge and it makes a subtle, but noticeable difference. There is no real hard edge to the phone and the move clearly helps Apple convince you that it is a smaller device that it actually is. The only real tell-tale sign is when the light catches the curvature of the glass in the sunlight.    

Pitched against popular Android devices, the extra screen space afforded to iOS 8 is certainly appreciated and we like it. It might be new territory for the iPhone, but this is something that the likes of Samsung has been doing for some time with the Note family.

The iPhone 6 Plus measures only slightly thicker than the iPhone 6 at 7.1mm, which by any measure is slim. It's a large device overall, however, measuring 158.1 x 77.8 x 7.1mm.

Those who pay attention will notice that the power button has moved to the side (a very Android thing, viz Sony) and that the volume buttons are now elongated rather than circular. Having the power button on the side makes it reachable when gripping the phone, as it would be a stretch to reach to the top.

Beneath the screen is the Touch ID home button, as found on the iPhone 5S. Apple might have made the screen bigger, but it isn't following Android down the no physical button path. That Touch ID button will play a bigger part in future payments using Apple Pay.

While the new look and bigger screen are likely to dominate a lot of the conversation, it what's on the inside that will make the biggest difference.

A new processor, the A8, and a new coprocessor, the M8, new Wi-Fi (802.11ac), LTE (VoLTE) and NFC, are worth writing home about. In our brief play we were impressed by the speed of which some of the bigger games opened.

That should make everything from loading games to surfing the web a lot quicker and it will be something we will be keen to check in more detail during our full review.

It certainly felt responsive in our play at the Apple event and we noticed nothing out of the ordinary compared to the iPhone 5S.

In the US you'll get Apple Pay, a quick payment system that will allow you to use hundreds of thousands of contactless payment points in the US. Apple has confirmed that it will be rolling out the service globally but haven't detailed when that will be.

READ: What is Apple Pay and how do you use it?

In a demo of the new service the feature works exceptionally well. Expect to be paying with your mobile a lot more in the future.

Apple is happy with the camera's performance on the iPhone 5S and it is sticking with the same image sensor for the iPhone 6. It did however add a few new tricks, thanks to improvements with the processor that powers it all.

Now you can take panoramic shots up to 43 megapixels, use a new feature Apple are calling Focus Pixel designed to give you better focusing, and benefit from HDR in video, slow-mo up to 240fps (twice the frame rate of the 5S), and a few other tricks like image stabilisation.

The iPhone 6 Plus gets optical image stabilisation, a popular feature that should improve low light performance, reducing shake on longer exposures. OIS has worked well for the likes of Nokia, and Apple is looking to repeat that trick on the iPhone 6 Plus. Again we weren't able to properly test the feature, but watching videos that Apple had pre-recorded with the phone look promising, very promising indeed. 

The iPhone 6 Plus also gets Burst Mode for the front-facing camera making taking a selfie a lot easier, and you just know that your kids are going to go stupid over that feature. 

Aside from new hardware, the iPhone 6 Plus also gets new software tricks, some of which will only be found on this device rather than the smaller iPhone 6. Trying to maximise the size as much as possible users will get landscape mode for the homepage, and a dedicated landscape mode for Mail, allowing you to replicate the iPad landscape mode with the list of your emails on the left and the actual email on the right.

There's also a new feature Apple are calling Reachability. Double soft tap on the TouchID button and the screen instantly gets chopped in half so you can reach the top without having to use a second hand. It feels like a solution to a problem that shouldn't be there, but clearly Apple's answer to the fact that people want big screens and still the ability to use it while carrying a coffee walking down the street. In use and it's handy but awkward. Maybe we just aren't used to the software jumping around to deal with the fact that we can't reach the top of the screen.

A repeat of the action reinstates the norm. 

The iPhone 6 Plus is an interesting device and one that will make many iPhone upgraders torn between screen sizes. The device size is undeniably large, even though it is thin, but the extra features like the bump in screen quality and resolution, and optical image stabilisation, will make a difference to some users.

We suspect that the iPhone 6 will be the most popular upgrade, the one that most will opt for in places like the UK and the US, however in Asia, where customers love big screens, this might allow Apple to really go up against the big screen competitors from Samsung and LG without fear of losing the size battle.

The iPhone 6 Plus is a monster that sits alongside the Samsung Galaxy Note 4 in terms of size. It will appeal to a specific audience wanting something bigger than a phone but smaller than an iPad, in the same way Android phablets have enjoyed popularity in recent years, or perfect for those that can't necessarily afford both a phone and a tablet. 

There are still plenty of questions to answer, like battery performance, how well new software features like Reachability and landscape mode work, but there's no denying that iPhone users now have a choice. For some, however, the iPhone 6 Plus may be too big to handle.