Apple has unveiled its largest most powerful tablet yet in the iPad Pro. It has an optional physical keyboard case and a stylus called the Apple Pencil, setting it directly against Microsoft's Surface Pro 3.

Apple has even got Microsoft to adapt its Office suite to work with its Pencil stylus and touch controls, for easier use. But with Microsoft nearly on its fourth iteration of the Surface Pro, can Apple's first big tablet compete?

We've laid out the two work-focused tablets side-by-side to see how they compare, what the differences are, and which device comes out on top.

The iPad Pro, as you'd expect from Apple, is perfectly minimal. Despite the large screen and four speakers, the unit is only 6.9mm thick and weighs 713g. The drilled speaker holes look premium, and the rounded edge finish appears to offer plenty of comfort.

The Microsoft Surface Pro 3 is thicker at 9.1mm and weighs in at 800g, despite having a slightly smaller screen. But in its defence, there's a lot of power crammed in and it has a built-in kickstand, which is ideal for getting work done. As you'd expect comparing a PC to a Mac the design is more angular and industrial, although this is not a bad thing in this case.

Apple says the iPad Pro is its most powerful iPad yet at 1.8 times faster than the iPad Air 2 and with 90 per cent faster graphic processing. That's thanks to the new A9X chip which comes with the M9 motion coprocessor. All that should last a full 10-hours on a charge, claims Apple.

Microsoft has various fouth-gen Intel Core options including i3, i5 and i7 coupled with up to 8GB of RAM and 512GB of storage. This is a proper computer crammed into a tablet form factor. Despite all the power, you should still get 9-hours of use.

The Apple iPad Pro comes with a 12.9-inch LED-backlit multi-touch display with a 2732 x 2048 resolution for 264ppi. The Microsoft Surface Pro 3 on the other hand, sports a 12-inch ClearType multi-touch display with 2160 x 1440 resolution for 216ppi.

This means you don't just get a larger display with the iPad Pro, but images should be sharper and crisper too thanks to the extra pixels per inch.

The iPad Pro sports an 8-megapixel camera on the rear with autofocus, f/2.4 aperture and a five element lens capable of 1080p video at 30fps. On the front is a 1.2-megapixel FaceTime HD Camera with f/2.2 aperture capable of 720p video.

The cameras on the Surface Pro 3 are the same on the front as the back, both offering 5-megapixels. These can manage 1080p quality video recording at 30fps.

The Apple iPad Pro runs Apple's latest iOS 9 mobile operating system. While this is arguably the equivalent of a Windows RT Surface machine, with limited access to mobile apps only, it could still work. Apple has enabled multiasking, supported by Microsoft Office and Adobe apps, that takes advantage of the touchscreen and Pencil interface. But you are still always going to be limited by not running the full Mac OS, and the inability to use the full run of applications available on desktop OS.

Microsoft Surface Pro 3 features full Windows 8.1 Pro and can be updated to Windows 10. By offering the full Windows experience, the Surface Pro 3 has the advantage of offering more choice to many, supporting all the applications you could use on a desktop PC. For those looking for more than a tablet the Surface will offer more.

Both the Apple iPad Pro and the Microsoft Surface Pro 3 feature cases that double as keyboards. The iPad Pro Smart Keyboard acts as a case and stand, using a magnetic connector for transferring power and data. The Surface Pro 3 can work with a Surface Pro Type Cover for physical backlit keys.

Both devices also feature stylus options. Apple's Pencil detects pressure, position and angle for varying line pressure and thickness. Microsoft's Surface Pen is pressure sensitive and features palm block tech so you can rest your hand on-screen as you write or draw.

For Apple both of these are optional extras, but the Surface Pro 3 comes with the stylus. 

The Surface Pro 3 offers a wider range of connectivity too, more like a laptop. It will accept microSD cards and offers a full-sized USB 3 connection, ideal for connecting external devices. There's also a Mini DisplayPort connection. The iPad Pro offers less, with only the Lightning connection.

The Apple iPad Pro has a larger screen with higher resolution, as well as a longer battery life. That said, the slightly heavier and thicker Surface Pro 3 packs in a lot more raw power and better front-facing camera, a built-in tilt stand, and a wider range of connectivity options.

Both tablets feature optional physical keyboards and pens. The design of the iPad Pro and Surface Pro 3 does vary, as expected. But both are premium and have their own taste appeal, so it may be a case of personal preference here.

It really comes down to if you need iOS or full Windows OS. The latter is going to offer the wider range of full apps and the flexibility of a full desktop OS, the iPad Pro might be somewhat restricted by offering mobile apps. The Surface Pro 3 and the iPad Pro both start at $799.

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Apple iPad Pro first-look: Trying out the Pencil and keyboard with the new bigger iPad