Chinese manufacturer OnePlus has finally revealed all the details of the OnePlus 2 - the succeeding device of the invite-only OnePlus One smartphone that graced us with its presence last year.

The company made a clever play with the OnePlus One - delivering an affordable handset but ensuring it was desirable by making it hard to get and a similar approach will occur for the OnePlus 2, with an invite system already in place.

READ: OnePlus 2 hands-on: The 'flagship killer' has arrived, and it's a beaut

The OnePlus 2 has been the subject of rumours since mid-2014 and while some specs were confirmed in advance, we now have all the nitty, gritty details, allowing us to compare old and new, spec for spec, to see what the differences are. The OnePlus One is now available to buy without an invite so should you put your cash there, or get yourself on the list for the OnePlus 2? Read on to find out.

The OnePlus One is described by the company as "the original flagship" killer. It is no small device measuring 153 x 76 x 8.9mm, but it offers a great, solid build quality given its price. The OnePlus One comes in Silk White and Sandstone Black finish options.

The OnePlus 2 on the other hand, measures 151.8 x 74.9 x 9.9mm so it is slightly smaller than its predecessor but a little thicker. It is also pretty weighty at 175g. The OnePlus 2 will be available in five finishes including the Sandstone Black of the OnePlus One. There will also be actual wood built Bamboo, Black Apricot, Rosewood and Kevlar.

In other design news, the OnePlus 2 introduces a central button on the front of the device, along with a fingerprint sensor on the rear. OnePlus said the fingerprint sensor will be "lightning quick", emphasising that it'll be able to unlock your device in less than half a second. It'll also store up to five fingerprint profiles.

OnePlus 2 also introduces USB Type-C charging port, which means it will be reversible for easy connection. Additionally, the OnePlus charging cable uses patented technology making the Type-A side reversible as well. In terms of build quality - we expect the same level as the original, if not better.

The OnePlus One features a 5.5-inch Full HD IPS display, which delivers a pixel density of 401ppi. This isn't as high as some of its competition, with many offering QHD displays, but it is big, sharp and offers the decent colour accuracy we look for in a higher-end screen. It's an LTPS (Low Temperature PolySilicon) LCD panel too, which is partly how the OnePlus One manages to last for so long on a single battery charge - it's a relatively recent power-saving manufacturing technique.

There was talk that the OnePlus 2 will step up the resolution to a QHD display like the majority of the other flagship devices available, but OnePlus stuck to a 5.5-inch Full HD IPS LCD display. We assume this is down to cost and given that we were impressed with the original's display, we aren't too disheartened. It does mean that the second version may not be quite as much of a flagship killer however.

Smartphone cameras are getting better and better, with many manufacturers bumping up the megapixels and altering the aperture to allow for better shots. The OnePlus One features a 13-megapixel rear snapper, which was slightly less than its flagship rivals at the time of launch, along with a 5-megapixel front camera.

For the £230 price, we felt the OnePlus One was a good performer in terms of camera. The rear camera was good in daylight, offering images with lots of detail, while the front camera was much better than many we had used at the time of review.

The OnePlus 2 claims to offer an improvement on the camera capabilities, as you might expect, but it doesn't do so in terms of megapixels. The front-facing snapper remains at 5-megapixels, while the rear camera sticks to 13-megapixels. The f/2.0 aperture remains from the previous device, as do the six lenses. The main difference is the introduction of an advanced OIS system, along with rear mounted laser technology, which OnePlus claims will sharpen and focus the camera in just 0.33 milliseconds.

The OnePlus One has a 2.5GHz quad-core Snapdragon 801 processor with 3GB of RAM and we were impressed with the speed and immediacy this delivered when we reviewed it. There is also a 3100mAh battery on board, which offered one and a half days of heavy use and two days of light use.

The OnePlus 2 raises the stakes in this department too with a 64-bit 8-core Qualcomm Snapdragon 810 processor under the hood. This means Adreno 430 graphics and fine-tuning to deal with that overheating issue some other flagships with this processor have faced. The new device will also offer 4GB of RAM and an increased battery capacity to 3300mAh so you should see an improvement on the already impressive life over its predecessor.

In terms of storage, the OnePlus One offers 16GB and 64GB variants with no microSD support for further storage expansion. The OnePlus 2 will also be offered in 16GB and 64GB variants, with the 16GB model featuring 3GB of RAM instead of 4GB.

OnePlus delivers internal specs that compete with Android's elite, for both the OnePlus One and the OnePlus 2, but their software doesn't follow the traditional Android path. Instead the OnePlus One features the CyanogenMod operating system found on other devices such as Oppo. It was based around Android 4.4.2, but is open source and dressed up a little differently.

The OnePlus 2 will be the first device to run on the company's own OxygenOS. This is based on pure Android 5.1 Lollipop. The result should be a buttery smooth experience with all the positives of running pure Android. OnePlus says it will offer "subtle customisations like on screen gestures, dark mode, the ability to switch between hardware and capacitive buttons and toggle quick settings are baked in throughout the OS." It will also be loaded with custom apps including camera, audio tuner and file manager.

The OnePlus 2 trumps the OnePlus One in a few areas including finish options, improved camera performance and hardware. But you would expect that from a succeeding device so this won't come as too much of a shock. A few things do remain the same though, such as the display and lack of microSD.

The addition of the fingerprint sensor and USB Type-C help make the OnePlus 2 more desirable than the OnePlus One, but there is one problem - you'll have to wait for it and you'll need an invite.

The OnePlus One was a great device when we reviewed it and while it may not sport the latest specs now, it is still a powerful handset for a great price. Plus, you no longer need an invite. Ultimately the decision between these two devices sits upon whether you are prepared to wait.