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Lego Boost review: Lego Boost is the crazy robot cat guitar kit you never knew you wanted

Cute kittens! Electric guitars! Dancing '80s robots! Lego Boost is a blast.

Scott Stein Editor at Large
I started with CNET reviewing laptops in 2009. Now I explore wearable tech, VR/AR, tablets, gaming and future/emerging trends in our changing world. Other obsessions include magic, immersive theater, puzzles, board games, cooking, improv and the New York Jets. My background includes an MFA in theater which I apply to thinking about immersive experiences of the future.
Expertise VR and AR | Gaming | Metaverse technologies | Wearable tech | Tablets Credentials
  • Nearly 20 years writing about tech, and over a decade reviewing wearable tech, VR, and AR products and apps
Scott Stein
5 min read

For the last week, I've been huddled over bags of Lego bricks, following instructions oh so painstakingly. Dozens of tiny connectors lay scattered at my feet.

The Good

Forms five unique creations out of the box, and can be customized; uses regular Lego pieces; programming possibilities are limited to what Lego offers, but offers lots of depth.

The Bad

Needs a tablet or phone (Android or iOS) to connect to in order to use (and get access to assembly instructions). Need to dismantle one robot before building another. In-app instructions can sometimes get confusing. Not compatible with Lego Mindstorms kits.

The Bottom Line

Lego's young kid-targeted robotics set isn't as deep as Mindstorms, but has a ton of things to do, and it's a lot of fun to play with.

Hours later, I made a farting robot.

Lego Boost isn't a regular Lego kit: it's a connected, programmable robotics set. It pairs with a tablet or phone with Bluetooth. It has motors and proximity sensors. And it might be the best all-in-one Lego kit I've ever seen. But it's definitely a challenge. And, in the last week, I've sucked down a Lego rabbit hole.

Unlike Lego Mindstorms, the brick company's "expert" line, Lego Boost aims younger, at kids 7-12. (There's another kit, Lego WeDo, that's similar but education-targeted.). Boost has a mix of standard Lego bricks and Technic-type pieces, which means that these robots can be enhanced or customized with other Lego pieces. That's a big deal.

Lego Boost is also a robot kit, and it's more advanced than you might think. A central Bluetooth-connected motorized hub with two separate modules come included. The hub drives motors that can lift arms, make treads move, or turn robot heads. One module has sensors that measure proximity and color. The other has an additional motor.

Lego Boost is your robot coding superkit

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840 pieces come in the kit for $160, which isn't bad by Lego standards. The kit can make more than one robot, too; in fact, the set has instructions for five main creations, and can be customized to others. Also, everything can be programmed with block-based coding tools in a connected phone/tablet app... which, by the way, you need to use Lego Boost.

So, here's how I built what I built.

Part one: Vernie

Two hours, and following over a hundred steps on the iPad app, I had a rolling robot straight out of an '80s movie. Vernie is adorable.

None of Lego Boost's robots can make sounds on their own, but your paired phone or tablet can make it sound like it has sound effects. The app has a giant sound board of hundreds of phrases and effects, ranging from pleasant greetings to a spectrum of flatulence. The vast (and sometimes confusing) app also can record new voice samples for some of its various parts.

Lego Boost has a lot of unlockable extras, and that's fantastic. I tested on a beta build with most parts unlocked already. I found it got a little confusing to know where to go next, though, and how to make things happen in different sections of the app. There are a number of minigame-like areas to make Vernie dance and move, and it's hard to figure out where to start.

But Vernie is the star of the show, and I could see paying $100 or more for him alone.


Rock on.

Lori Grunin/CNET

Part two: Electric guitar

It's a little crazy that this kit can also build a playable guitar-like toy, complete with a whammy bar. I built that one next around the same core and sensors as Vernie the robot.

Several hours later, I had a mini-banjo-like electric guitar replica. It doesn't have its own speakers, but it plays sound via a connected phone or tablet, like a little amp. The coolest part is that it has a strummable lever, and the moving fret-like control near the top works by triggering distance sensors that convert that into notes.

This is where my son was no longer interested in building... but he liked playing it when I was done.

Much like Vernie, the guitar has lots of extra modes, and ways to reassign sound effects to rock, acoustic, bird tweets, machine sounds or more farts.


I only half-completed the kitten.

Lori Grunin/CNET

Part three: Little kitty

I tried for a third model, which is about as much as my limited time with Boost could afford. 180 steps in, I got the robotic head and torso of a cat. It actually follows a little cat toy and makes purring sounds. The kitten is as amazing as all the other creations, and it's hard to believe it came from the same bricks.

At this point, I had hit Lego exhaustion.


You must undo what you have done.

Lori Grunin/CNET

Learning to let go and love the chaos

Taking apart each model to build a new one isn't easy, I found... emotionally, I mean. I wanted to hold onto my creation. I didn't want to start over. I wanted to preserve the pieces in their original numbered dozen or so bags.

I realized I was doing Lego wrong. I was attached to the little bags they came in. That guided me through the first robot, Vernie, but after that the set asks for pieces from all over the place...including the robot you just made.

I had to learn to let all the pieces mix... to sort them freeform... and to let go of my lovely robot friend.

If you're a completionist, undoing and redoing Lego Boost might be a challenging thing for you. If you like exploring, you're set. Also, my kid was fine, and didn't stress out like I was doing.

As my wife said to me, "this is a microcosm of your life."

Technical details: Boost uses six AAA batteries, and needs a phone or tablet to work. Battery life worked for about a week of heavy usage during this review. This is a more advanced level of Lego construction with lots of little connectors and a few wires, so it's this definitely not for preschoolers.

The best Lego kit for the holidays (if you're up for some robotics)

I love Lego Boost. It sucked me in, and its five or so main challenges are more than worth the price. Then there's all the extra stuff, which I've barely scratched the surface on: extra challenges, all the free-form block-based programming, and the chance to just take the Lego pieces and be creative.

This is a stellar collection of Lego fun for the price, even if the price seems high. I'd rather have this $160 kit than three $50 kits that aren't necessarily even robotic. Yes, you need a phone or tablet to enjoy Lego Boost. (And to that end, it would be great if Lego adds support for the Amazon Fire tablet line, which can be purchased for as little as $50.) But assuming you have that, this is like a more affordable Lego Mindstorms kit that younger kids can play with, too.


Lego Boost

Score Breakdown

Design 8Features 9Performance 7