We’re big fans of HP’s current range of Windows 10 laptops, convertibles and 2-in-1 detachables here at Expert Reviews, and there’s now a new member of the family – the Envy x2.This is no ordinary Windows portable, however: it’s one of the first wave of Qualcomm Snapdragon-powered machines, dubbed “Always On PCs”, and it’s set to offer Intel-busting battery life as well as gigabit-class 4G connectivity.READ NEXT: The best laptops of 2017 – our favourite portable PCsHP Envy x2 review: Key specifications and priceDisplay: 12.3in, 1,920 x 1,280Weight: 0.7kg (without keyboard cover)Processor: 2.14GHz Snapdragon 835 with X16 gigabit 4G modemRAM: Up to 8GBStorage: Up to 256GBOperating system: Windows 10 S (upgradeable to Windows 10 Pro before 30 September 2018)Price: TBCRelease date: Spring 2018HP Envy x2 review: Key features and first impressionsThe HP Envy x2, on the face of it, is just another 2-in-1 detachable. That means it’s a rival to the Microsoft Surface Pro. It has a 12.3in, 1,920 x 1,280 resolution display, a keyboard cover that detaches and stylus support, with full Windows Ink certification.And it’s a pretty nice-looking machine, too. The tablet is 6.9mm thin and 0.7kg light, with a vibrant-looking touchscreen and, although the tablet doesn’t have a kickstand built into it, you do get a kickstand integrated into the keyboard cover, which wraps all the way around the tablet and splits into two at the rear, with the top half hingeing down to prop the tablet up on a desk or (a little less securely) on your lap.The keyboard itself felt comfortable to type on in the short time I had with the device, and the huge touchpad was pretty responsive, too. Windows 10 and its core applications all ran without lag – just as they would on an Intel-based machine, in other words.It isn’t the best-connected device from a physical perspective. You get a USB Type-C port on the left edge of the machine and a 3.5mm jack on the right – and that’s your lot. Apart from the magnetic keyboard connector on the bottom edge, the HP Envy x2 is pretty bare.But it’s the connectivity and battery life promised by the Snapdragon 835 processor inside the Envy x2 that’s the big news here. HP says the Envy x2 will deliver up to 20-hours of video playback, which in my experience is significantly longer than the current generation of Intel-based laptops. It will also have gigabit 4G connectivity, with support for both physical and E-SIM connectivity.That’s exciting stuff, but it’s how well this works with third-party apps that will be critical to the success of these types of devices such as the HP Envy x2. Yes, it runs Windows 10 (Windows S, in fact, but upgradeable to Windows 10 Pro until September 2018) and, yes, it should run most of the apps that Windows users love and need to use for work. Whether it will run applications such as Photoshop effectively, though, will be critical to how many users will actually want to buy one of these machines.While the core Windows apps have been natively developed for the Qualcomm 835 chipset, many other win32 applications will need emulation to run. Aside from the performance implications, it’s something that could undermine battery life. It’s also worth noting that 64-bit Windows apps aren’t supported yet at all.One thing running intensive apps on the HP Envy x2 won’t do, however, is spin up annoying whiny fans. The Envy x2, just like the Asus NovaGo, is completely fanless.HP Envy x2 review: Early verdictThere are no prices available for the HP Envy x2 yet so I can’t make a call on value at this time, but if it’s anything like the Asus NovaGo, it should be more cost-effective than buying a full Intel-based equivalent.That would make sense, in fact: in a market dominated by Intel machines in order to make inroads you have to undercut on price, so I’d expect the HP Envy x2 to do just that and come in at significantly below £1,000.Beyond that, I can’t say exactly how good the machine is likely to be just yet. It all comes down to how well it runs the applications we all need for work and play. If it can pull that feat off and combine it with the promised 20-hour battery life, Intel will have it all.