Asus Chromebook Detachable CM3 review: Duet redux


All in all, the Chromebook Detachable CM3 from Asus is a nice package. It is a 10.5-inch tablet with magnetically attached cloth cover and stand. Her $389.99 as tested, meaning it’s priced way below all types of convertible Chromebooks. I’m not the first to make this comparison, but it’s a slightly more expensive and slightly more exclusive version of the $269 (currently $269) Lenovo Chromebook Duet that impressed me so much last year.

I think the CM3 is a slightly worse purchase than the Duet for most people looking for a secondary device, or a small Chromebook for a college student. The CM3 offers a few noticeable advantages over the Duet, but I’m not sure they’re worth $100. While features like a double-folding kickstand, docked stylus, and headphone jack are nice to have, none of them are as central to a device’s user experience as the processor. And while $269 is an acceptable price to pay for a tablet with a MediaTek chip, $389.99 is a boost.

That said, I don’t have many issues with this Chromebook. It’s just in a weird place.

My test unit includes 128 GB of storage, 4 GB of RAM, a 10.5-inch 1920 x 1200 display and a MediaTek 8183 processor. It has a 64 GB version on it: $369.99 also. 64GB isn’t a lot of storage (and there’s no microSD card slot for expansion on the CM3), so my setup is the one I’d recommend to most people.

The most important thing to know about the CM3 before buying it is the size. It’s small, with only a 10.5-inch screen. This brings advantages and disadvantages. On the one hand, it’s quite slim and portable, only 0.31 inches thick and 1.1 pounds (2.02 pounds with the keyboard and stand attached). It’s one of those things I could easily carry in my bag.

On the other hand, a 10.5-inch screen is cramped for a desktop OS like Chrome OS (although it’s bright enough for outdoor use, and I appreciate that it has a 16:10 aspect ratio – 16:9 would unbearable for me in this size). But it was too small for me to use comfortably as a work driver. I had to zoom out far to see everything I needed in my Chrome windows.

It also means there’s only so much room for the keyboard deck, which is also cramped. Especially the touchpad is small. However, the keyboard itself is more spacious than the Duet’s – it has a surprising amount of travel and a satisfying click. While the small keys are a bit of an adjustment, none are small enough to be unusable.

Small doesn’t mean cheap, and the build of the CM3 is generally quite sturdy. The palm rests and detachable keyboard feel a bit tacky, but the tablet itself is aluminum (with “diamond-cut edges,” according to Asus). The magnetic cover is made of a woven fabric and is very similar to the cover of the Chromebook Duet. The cover is included in the price of the CM3, which is not the case with some detachable devices (such as Microsoft’s Surface Go line).

A USI stylus is located in the top right corner of the chassis – it sits firmly in it, so you need a nail to pull it out. It’s small and not my favorite stylus I’ve ever used, but it’s there and it works. The Duet supports USI styluses, but there isn’t one, so that’s an advantage of the CM3.

The main way the CM3 is unique to other detachable devices is that the stand can be folded in multiple ways. That is, you can fold it far when using the tablet as a laptop, or you can flip the tablet vertically and fold the stand horizontally. This is a cool feature I haven’t seen before, and it works – I was never afraid the CM3 would tip over in either direction.

On the other hand, the only real use case I can think of is for the horizontal position video calls where you don’t need to have the keyboard plugged in and the good thing is that the camera is on the side of the screen. You can form your own opinion, but I prefer to use an iPad or special tablet and have the camera in the right place.

My device had some fraying around the edges of the keyboard, which was disappointing to see on a brand new device, even at this price. The stand cover also slipped off the tablet a few times while I was adjusting the height, which never happened with the Duet.

Speaking of convertibility, the CM3 has a two-megapixel front camera and an eight-megapixel rear camera. Both cameras deliver a surprisingly reasonable image. I wasn’t too fatigued when I was on a video call outside, nor was I too grainy in low light. That said, the dual-camera setup is another cool-sounding feature that’s probably not the most pragmatic: the rear camera isn’t good enough for real-life photography of any kind, and its best use case is probably for shooting. pictures of a blackboard in the classroom. It also takes a few seconds for the CM3 to switch between cameras (it’s not nearly as fast as on an iPhone, say), so it wouldn’t have saved me a lot of time just pulling out a phone.

The Asus Chromebook Detachable CM3 closed with the camera facing up, seen from above.

If you look closely, you can see the fold running in both directions.

The Asus Chromebook Detachable CM3 keyboard seen from above.

A magnet on the top of the keyboard attaches to the bottom of the tablet and lifts the deck off the ground slightly.

The CM3’s MediaTek MTK 8183 is a hybrid chip mainly used in Android tablets. (It’s a different MediaTek chip than the one that was in the Duet last year, but very similar to the one in Amazon’s new Echo Show 8 smart display.) It’s far from the most powerful processor you’ll find in a Chromebook, but that’s by design – battery life will be a higher priority for many people considering a device as portable as the CM3.

The battery life is in fact excellent. I spent an average of 12 hours 49 minutes continuously running the CM3 through my normal workload of Chrome tabs and Android apps, including Slack, Messenger, Twitter, Gmail, Spotify, and the occasional Zoom call with the screen on medium brightness – over an hour longer than I saw from the Duet with the same workload. This is already a heavier load than many people might want the CM3 to endure, so you may get even more time between charges. The 45W USB-C adapter squeezed the CM3 to 40 percent in an hour, making it much faster than the Duet’s flimsy 10W charger.

That battery life doesn’t come for free, though, and the CM3’s performance was a mixed bag. For example, it works fine in Chrome, albeit with a little bit of sluggishness when switching tabs and resizing windows, as well as other Google services like Gmail, Docs, Drive, Calendar, and Meet (and it comes with a free 12-month 100 GB membership to Google One for the rest of this year). Gaming is fine too – Flip Legends and samples were both smooth and stuttering whether the CM3 was plugged in or running on battery.

I also think that Chrome OS’s tablet mode, which supports the CM3, has gotten pretty good. It uses Android-like gesture controls that can help flatten the learning curve for new Chromebook users. For example, swiping up takes you to the home screen and swiping right between web pages. You have access to a version of Chrome specifically for tablets that makes it easy to open, close, and reorder tabs with drag, swipe, and large buttons. It’s not like using an iPad, but I think it’s a smoother experience than Windows’ tablet mode (especially in Chrome).

All you have to do to toggle tablet mode on and off is to toggle the keyboard on and off – it takes a second and my windows didn’t always go all the way back to the way I arranged them when I put the keyboard back in on, but it’s generally a pretty smooth affair.

But the CM3 didn’t perform well on every task I needed. Sometimes when I tried to use Slack or Messenger over a stack of Chrome tabs, something would crash. Zoom calls were possible – which is more than can be said for some budget Chromebooks – but I was delayed between audio and video inputs. Slack froze and crashed quite often, and Spotify crashed a few times as well.

The Asus Chromebook Detachable CM3 open, tilted to the left.  The screen shows a cartoon cityscape on a pink background.

Access all kinds of Android apps through the Google Play Store.

Editing photos really got me into trouble. Lightroom was basically unusable on the CM3 with only a few things running in the background – I was trying to edit a batch of about 100 photos and was only able to run through a few before the program crashed. I tried to switch to Google Photos, which also eventually crashed, and ended up having to do everything in Gallery. Of course, not everyone will edit photos on their Chromebook, or push them as hard as I do on this one, so it’s a matter of knowing your own needs.

Speaking of Zoom meetings, the dual speakers are okay for Zoom conversations, but not too much more. The songs I played had stronger percussion than I sometimes hear from laptop speakers, but overall it was thin and tinny. The microphone seemed to work fine and had no trouble picking up my voice on calls.

This was a difficult product to score. I think the CM3 is a great device. And it offers a few advantages over the Chromebook Duet that justify it costing a little more. I’d probably buy it through the Duet myself for just the keyboard if I was looking for this type of device – the versatile kickstand, built-in stylus and decent build quality are nice perks too.

But “if I was looking for this type of device” does some heavy lifting in that sense. I’m not looking for a MediaTek device, and there’s a reason I’m not either. The battery life is impressive, sure, but it’s just not enough horsepower for the workload I need. And if you’re someone whose needs are right for this low-power processor (and there are plenty of these people in the world), I really think $389 is on the high side of what you should be spending.

Sure, the CM3 has a (just okay) stylus, a kickstand with a funky fold, slightly better battery life, and an extra port. But it’s also comparable to or slower than the Duet on most tasks I’ve tried, the sound is worse and it’s thicker and heavier. Given all of this, I’m not convinced that the CM3’s perks are worth $100 to most people shopping in this category.