You don't need a Desk Dock or Lap Dock to connect the Elite x3 to peripherals. You can use a USB-C adapter for your display's VGA, HDMI, or other input. (HP sells a USB-C-to-VGA adapter for $19, but nothing for HDMI, DisplayPort, MiniDisplayPort, or DVI video ports, all of which are newer than the still nearly universal VGA.) Or you can use Wi-Fi to drive a display with Miracast (WiDi) wireless connectivity built-in or with a Miracast receiver attached. (Such a Miracast display is most likely to be a TV.)
Bluetooth roulette: Windows 10 Mobile isn't very helpful in distinguishing among Bluetooth devices when you try to pair a keyboard or mouse. All devices in range show up, most marked as simply "Accessory."
The Elite x3 also supports Bluetooth keyboards and mice. But be warned that Windows 10 Mobile is pretty stupid about Bluetooth devices, so you'll get a list filled mainly with ones named "Accessory." They could be computers, smartphones, headsets, keyboards, mice, earbuds, or headphones. Some will be more clearly named; my Apple Magic Mouse showed up as Mouse, for example. Even then, in an office with lots of Bluetooth devices, you won't know which "Mouse" is yours.
Users at a minimum will definitely need to carry adapter cables for displays. Because Bluetooth keyboards and mice are not standard-issue outside Mac environments, users may want to carry those devices or a spare Desk Dock when they travel. They could buy a Lap Dock, but then why not issue them a laptop in the first place? It will cost less and provide more capability.
The smartphone designed for the Hulk
As a smartphone, the Elite x3 is a beast. It's too large -- 16 percent larger than a Galaxy Note 5 and 9 percent larger than a iPhone 7 Plus, the leading phablets -- to be used single-handedly, so you'll need both hands free to work with it. It's also heavy: 6.8 ounces, or 14 percent heavier than the Note 5 and 8 percent heavier than the iPhone 7 Plus. The HP Elite x3 should be the size of the iPhone 7 or Galaxy S7 to be used widely as a smartphone; phablets are popular but still not the main preference of users.
Further, the Elite x3 doesn't support any advanced security-access mechanisms like a fingerprint reader, as business-class devices like the Apple iPhone and Samsung Galaxy S series do.
Otherwise, it's a nice device, with a good (6-inch) screen and good battery life, plus support for Qi contact charging. The Elite x3 is an unlocked GSM phone, so it works on AT&T and T-Mobile networks in the United States, both 3G and LTE. (Verizon and Sprint users are left out in the cold.)
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