Surface Pro: The evolution of Microsoft's hybrid tablet PC

Microsoft's Surface Pro range of Windows tablet/laptop hybrids officially launched in February 2013, following a trailer at the Windows 8 and Surface RT event the previous October.

The first Surface Pro, originally called 'Surface with Windows 8 Pro', was a premium Core i5-based device costing $899 with 64GB of storage or $999 with 128GB, and you had to pay another $119.99 or $129.99 for a Touch Cover or Type Cover keyboard. This set the tone for the marque: high-quality, high-cost hardware, designed to showcase a new form factor and encourage OEMs to take the idea and run with it.

The following images examine how the Surface Pro has developed over the years.

Taking a leaf out of Apple's iPad nomenclature book circa 2012, Microsoft's fifth-generation Surface Pro -- announced on 23 May 2017 -- is marketed as 'the new Surface Pro', although inevitably it's already widely known as the 'Surface Pro 5'. From now on, we'll call it the Surface Pro '5'.

Read Ed Bott's review of the 2017 Surface Pro

Since its launch in 2012, Microsoft has built the Surface brand into a $1bn-plus business. Note that Surface revenue in the above graph includes proceeds from Surface, Surface Pro, and Surface Book (hybrid), Surface Laptop (notebook), Surface Studio (AIO desktop), and Surface Hub (presentation/collaboration screen) devices.

There have been persistent rumours of a smartphone or phablet format Surface device based on Windows 10 Mobile, but nothing has yet broken cover.

Read more Surface reviews

• Microsoft Surface 3 review: The Pro 3's Atom-hearted brother
• Microsoft Surface Book review: High-quality premium-priced 2-in-1 hybrid
• Surface Laptop: A trip on the Windows 10 S express you'll end quickly
• Microsoft Surface Studio, First Take: An appealing all-in-one debut, but the price is high
• Microsoft Surface Hub: Hands-on with the giant, expensive collaboration screen

Over the years, the Surface Pro has expanded screen real estate and resolution, while getting lighter and slimmer. Compared to its first-generation 10.8-inch predecessor, the 12.3-inch Surface Pro '5' delivers 28.4 percent more pixel density, 126g less weight and shaves 5mm off the thickness.

The original Surface Pro came with Windows 8 Pro, while subsequent models have run Windows 8.1 Pro (Surface Pro 2 and 3) and Windows 10 Pro (Surface Pro 4 and '5').

The original Surface Pro ran on a third-generation (Ivy Bridge) Core i5 processor with a TDP (Thermal Design Power) of 17W and required two (fairly noisy) fans to keep cool.

Since the Surface Pro 2, the maximum TDP has been 15W. The single-fan Surface Pro 3 suffered from overheating and fan noise issues, leading Microsoft to implement a hybrid liquid/fan cooling solution in the Surface Pro 4. The 2017 Surface Pro '5' with 7th-generation (Kaby Lake) Core m3 and Core i5 CPUs is entirely liquid cooled, although the Core i7 configuration requires additional fan cooling.

Performance has, of course, improved over the Surface Pro generations. Shown here are 3DMark Ice Storm Unlimited scores for the Core i5 versions of each generation. The CPU/GPU combinations are:

RAM options have increased from one-size-fits-all 4GB of DDR3 memory in the original Surface Pro to 4GB, 8GB, or 16GB of LPDDR3 in the three most recent models. Microsoft does not design the Surface Pro for upgradability: you've always had to specify the amount of RAM you'll need at purchase time.

The original Surface Pro was widely criticised for its poor battery life, but Microsoft (and its component suppliers) have steadily improved performance in this critical area.

The battery life figures for the Surface Pro 3, 4, and '5' are Microsoft's estimates for video playback time with wi-fi on and auto-brightness disabled (on a Core i5/8GB RAM/256GB SSD device); the figures for the Surface Pro and Surface Pro 2 are averages from multiple reviews.

Unless you run demanding workloads with screen brightness turned right up, the latest Surface Pro model should give you all-day (that is, over eight hours) battery life.

Ease of access to the chassis and upgradable components are not a feature of the Surface Pro range, to say the least. The highest repairability score from iFixit is 2/10, for the Surface Pro 4 (you can, if you're brave, replace the SSD). All other models get a paltry 1/10.

Read iFixit's Surface Pro teardowns

• Surface Pro
• Surface Pro 2
• Surface Pro 3
• Surface Pro 4
• Surface Pro '5'

A key adjunct to the Surface Pro is the Surface Pen, which has evolved from a Wacom-made 256-pressure-level stylus in the Surface Pro to a sophisticated N-Trig pen with 4,096 pressure levels, 21ms latency, 9g activation force, tilt support, and three different tips, all of which makes for natural-feeling inking and shading.

Since the Surface Pro 3, the Pen has included a Bluetooth option where a button click opens OneNote on the tablet. With the Surface Pro 4, the ability to take a screenshot and open Cortana was added to this now-customisable 'magic button'.

The Surface Pen was bundled with the tablet until the Surface Pro '5', but is now sold separately for £99.99 in the UK or $99.99 in the US.

Hybrid tablet/laptops with a kickstand design are commonplace nowadays, which is a testament to the influence of the Surface Pro range.

However, the first iteration was a limited affair, supporting just one, pretty upright (22-degree), angle. Since then, Microsoft's kickstand has developed into a versatile piece of engineering, and now supports multiple positions up to 165 degrees in the Surface Pro '5'. Many users still find the 'lappability' of kickstand designs problematical, however.

Although the Surface Pro has turned out to be good business for Microsoft, a major reason for its introduction was to encourage the company's hardware partners to take the form factor and run with it -- which they have done. A recent ZDNet roundup featured examples from Chuwi, Dell, Asus, Samsung, Huawei, Lenovo, and HP, and also noted that "It's hard not to look at the iPad Pro and think it was introduced at least partly because of competitive pressure from the Surface family of devices".