surface pro 4
The Surface Pro 4.

Microsoft took on the iPad Pro head-on Tuesday with an update to its Surface tablet line. The long-rumored Surface Pro 4 promises to combine a laptop and a tablet into one form factor, a long-standing goal of the Surface line and one that looks closer than ever with a redesign of the device.

Sporting an Intel Skylake chip, the Pro 4 has greatly boosted speed over its predecessor. Microsoft states it is 50 percent faster than Apple's MacBook Air and 30 percent faster than the Surface Pro 3. Options of up to 16GB RAM and 1TB of storage put the Surface Pro 4 on equal footing with the latest laptops. The tablet as a whole is 8.4mm thick.

The Surface accessories also have been updated. A new dock offers four USB 3 ports, two 4k DisplayPorts and Ethernet. The keyboard has been upgraded with a new glass trackpad. A fingerprint reader inside the keyboard allows for Windows Hello authentication, but face recognition is built right into the tablet.

Microsoft is also offering a new thin-bezel screen. The Surface Pro 4 comes in 12.3 inches with 267ppi resolution. A 1.1mm backlight and photo-aligned oxide display all add up to what Microsoft is claiming is the thinnest optical stack anyone can ship, making writing easier than ever.

The Surface Pro 4 also boasts an upgraded stylus to include an eraser at the other end, besting the Apple Pencil before it hits the market with easy access to correction functionality. It can distinguish 1,024 levels of pressure, meaning a smooth writing experience, while a year of battery life avoids the device cutting out during writing. A magnetic latch attaches the pen to the device when needed.

Whether consumers actually want to combine two rather different devices remains to be seen, but the numbers suggest Microsoft may be on to a winner: In fourth-quarter 2015 results, Microsoft highlighted the Surface line as one of its strengths, with revenue up 117 percent to $888 million. Furthermore, a report from analyst firm IDC in August expects to see the 2-in-1 tablet sector grow by 86.5 percent to 14.7 million units shipped in 2015, while Microsoft currently leads this category.

The Surface Pro 4 will be available from $899 and ships Oct. 26.