I just got a 15.6″ 4K resolution Desklab portable touchscreen monitor [1]. It takes power via USB-C and video input via USB-C or mini HDMI, has touch screen input, and has speakers built in for USB or HDMI sound.
Table of Contents
PC Use
I bought a mini-DisplayPort to HDMI adapter and for my first test ran it from my laptop, it was seen as a 1920*1080 DisplayPort monitor. The adaptor is specified as supporting 4K so I don’t know why I didn’t get 4K to work, my laptop has done 4K with other monitors.
The next thing I plan to get is a VGA to HDMI converter so I can use this on servers, it can be a real pain getting a monitor and power cable to a rack mounted server and this portable monitor can be powered by one of the USB ports in the server. A quick search indicates that such devices start at about $12US.
The Desklab monitor has no markings to indicate what resolution it supports, no part number, and no serial number. The only documentation I could find about how to recognise the difference between the FullHD and 4K versions is that the FullHD version supposedly draws 2A and the 4K version draws 4A. I connected my USB Ammeter and it reported that between 0.6 and 1.0A were drawn. If they meant to say 2W and 4W instead of 2A and 4A (I’ve seen worse errors in manuals) then the current drawn would indicate the 4K version. Otherwise the stated current requirements don’t come close to matching what I’ve measured.
Power
The promise of USB-C was power from anywhere to anywhere. I think that such power can theoretically be done with USB 3 and maybe USB 2, but asymmetric cables make it more challenging.
I can power my Desklab monitor from a USB battery, from my Thinkpad’s USB port (even when the Thinkpad isn’t on mains power), and from my phone (although the phone battery runs down fast as expected). When I have a mains powered USB charger (for a laptop and rated at 60W) connected to one USB-C port and my phone on the other the phone can be charged while giving a video signal to the display. This is how it’s supposed to work, but in my experience it’s rare to have new technology live up to it’s potential at the start!
One thing to note is that it doesn’t have a battery. I had imagined that it would have a battery (in spite of there being nothing on their web site to imply this) because I just couldn’t think of a touch screen device not having a battery. It would be nice if there was a version of this device with a big battery built in that could avoid needing separate cables for power and signal.
Phone Use
The first thing to note is that the Desklab monitor won’t work with all phones, whether a phone will take the option of an external display depends on it’s configuration and some phones may support an external display but not touchscreen. The Huawei Mate devices are specifically listed in the printed documentation as being supported for touchscreen as well as display. Surprisingly the Desklab web site has no mention of this unless you download the PDF of the manual, they really should have a list of confirmed supported devices and a forum for users to report on how it works.
My phone is a Huawei Mate 10 Pro so I guess I got lucky here. My phone has a “desktop mode” that can be enabled when I connect it to a USB-C device (not sure what criteria it uses to determine if the device is suitable). The desktop mode has something like a regular desktop layout and you can move windows around etc. There is also the option of having a copy of the phone’s screen, but it displays the image of the phone screen vertically in the middle of the landscape layout monitor which is ridiculous.
When desktop mode is enabled it’s independent of the phone interface so I had to find the icons for the programs I wanted to run in an unsorted list with no search usable (the search interface of the app list brings up the keyboard which obscures the list of matching apps). The keyboard takes up more than half the screen and there doesn’t seem to be a way to make it smaller. I’d like to try a portrait layout which would make the keyboard take something like 25% of the screen but that’s not supported.
It’s quite easy to type on a keyboard that’s slightly larger than a regular PC keyboard (a 15″ display with no numeric keypad or cursor control keys). The hackers keyboard app might work well with this as it has cursor control keys. The GUI has an option for full screen mode for an app which is really annoying to get out of (you have to use a drop down from the top of the screen), full screen doesn’t make sense for a display this large. Overall the GUI is a bit clunky, imagine Windows 3.1 with a start button and task bar. One interesting thing to note is that the desktop and phone GUIs can be run separately, so you can type on the Desklab (or any similar device) and look things up on the phone. Multiple monitors never really interested me for desktop PCs because switching between windows is fast and easy and it’s easy to resize windows to fit several on the desktop. Resizing windows on the Huawei GUI doesn’t seem easy (although I might be missing some things) and the keyboard takes up enough of the screen that having multiple windows open while typing isn’t viable.
I wrote the first draft of this post on my phone using the Desklab display. It’s not nearly as easy as writing on a laptop but much easier than writing on the phone screen.
Currently Desklab is offering 2 models for sale, 4K resolution for $399US and FullHD for $299US. I got the 4K version which is very expensive at the moment when converted to Australian dollars. There are significantly cheaper USB-C monitors available (such as this ASUS one from Kogan for $369AU), but I don’t think they have touch screens and therefore can’t be used with a phone unless you enable the phone screen as touch pad mode and have a mouse cursor on screen. I don’t know if all Android devices support that, it could be that a large part of the desktop experience I get is specific to Huawei devices.
One annoying feature is that if I use the phone power button to turn the screen off it shuts down the connection to the Desklab display, but the phone screen will turn off it I leave it alone for the screen timeout (which I have set to 10 minutes).
Caveats
When I ordered this I wanted the biggest screen possible. But now that I have it the fact that it doesn’t fit in the pocket of my Scott e Vest jacket [2] will limit what I can do with it. Maybe I’ll be buying a 13″ monitor in the near future, I expect that Desklab will do well and start selling them in a wide range of sizes. A 15.6″ portable device is inconvenient even if it is in the laptop format, a thin portable screen is inconvenient in many ways.
Netflix doesn’t display video on the Desklab screen, I suspect that Netflix is doing this deliberately as some misguided attempt at stopping piracy. It is really good for watching video as it has the speakers in good locations for stereo sound, it’s a pity that Netflix is difficult.
The functionality on phones from companies other than Huawei is unknown. It is likely to work on most Android phones, but if a particular phone is important to you then you want to Google for how it worked for others.
On the 4K question – power supply requirements (what current needs to be supplied safely) will often be significantly larger than average power usage, so measuring the usage doesn’t really tell you much. Probably be easier to use a 10x magnifier and just count LCD pixels to see if it is even capable of 4K. Bit poor that there is no labelling.