The first Lego Boost product is what the company is calling a "creative toolbox," which contains three Boost bricks plus 840 other Lego blocks. The core unit is the Move Hub, which contains a six-axis tilt sensor, two input and output ports, a power button and a light that changes color. It's powered by six AAA batteries and is covered in the usual Lego studs so that kids can build on top of it. Other Boost bricks include a combination color and distance sensor and an interactive motor. The motor has a tachometer in it, which tells the software how much it's turned and at what speed. This, Lego says, allows for finite control and more minute movements.

The set also comes with building instructions for five models: Vernie the Robot, Frankie the Cat, the Guitar 4000, the Multi-Tool Rover 4 (essentially construction-type vehicle), and an Autobuilder, which is a machine that builds tiny Lego creations for you. But before you can build any of those, you have to download the companion Boost app. The app is essential to the process; it has all of the instructions plus it's the key method of programming and interacting with the Boost creations.

Once you get the app, it will ask you to create a "Getting Started" vehicle, which is really just the three Boost blocks put together. This is basically a tutorial mode that walks the kids through the Bluetooth pairing process and familiarizes them with the app and the hardware. They'll immediately get into the coding interface -- which consists of drag-and-drop modules -- and learn how to make their little vehicle move around. Then the kids can choose whichever of the five models they want to build. When they do, the app asks them to build their creation step by step.

With Vernie the Robot, for example, you'll first create the head, then the upper torso, shoulders and then you'll be instructed to plug in the Move Hub. Press the green button, and the robot comes to life. Because the app knows you're building the robot instead of the other creations, it immediately assumes the character of Vernie and start talking, asking for your name and introducing itself. It will then suggest going for a drive, but because you haven't built his tracks yet, it will just vibrate. Vernie will then prompt you to complete his build. Simon Kent, Lego Boost's lead designer, joked that this is probably the first time a Lego creation has told you to continue building it.

Indeed, Vernie has a lot of built-in charm. Its head moves when it talks to you, and when you shake its hand (thus triggering the tilt sensor), it greets you like a friend. Kent says this is part of what makes the Boost toys feel so personal and alive. "You don't need to program those aspects in or code from scratch," he says. "It's much easier than Mindstorms."

From there, it's a matter of coding the robot to do what you want. The app has a freeplay area that lets you code your creation with all kinds of different modules -- the green ones indicate movement, the purple is for speech (it uses the tablet's microphone and speakers for audio) and the blue ones are for action. The code is horizontal, and runs from left to right, so it's easy for kids to grasp. Plus, the modules are icon-, not text-based, so you don't have to know how to read.

What I really like about the Boost app are the activities. There's a Western-style one, for example, in which you can outfit Vernie with a handlebar mustache and a little shooter gun. You can also build a target for Vernie to shoot at. The app will then prompt you to compile a code string where Vernie will shoot whenever it hears a clap. Start the activity, and Vernie will pivot around emitting a radar-like sound. Clap, and Vernie will stop and shoot its tiny Lego bullet. I tried this out in a demo, and it worked quite well, though sometimes it would trigger even at the slightest sound. "That could just be because of the app," said Kent, adding that it was still in beta.

As the child plays through these activities, they'll learn about new coding functions. So the more activities they do, the more coding modules they'll accumulate. One particularly funny Vernie activity is to, well, pull its finger. When it does, it'll emit a farting sound. "It's immature, but kids love it," said Kent. There's another one in which Vernie dances to music, and whenever you clap, it'll spin. The clap will even activate the light on its chest to change like a disco ball.

The other Boost creations are pretty great too. The Guitar 4000 lets you play your own music, the MultiTool Rover is a vehicle that can be any tool you wish and the AutoBuilder uses a grid reference palette to put together Lego bricks for you. I was particularly taken with Frankie the Cat. It starts off as a kitten, which meows and purrs as you cradle it. From there you can program it to instill in it all the various characteristics of a cat.

Feed it from a "milk bottle" and it will purr even more (the milk bottle has an orange tip, which triggers the color sensor in the cat's "mouth." Give it too much milk, and it will fart. Lift it by its tail and it will meow angrily. Its eyebrows twitch and its tail wags. You can even leave the program running in the background so you have to figure out what is it that the cat is meowing after -- does it want milk, or a rub? "It's a nurturing, Tamagotchi-style of play," said Kent.

But what makes Lego Boost especially amazing is that you can use it with your existing Lego bricks. That means that if you have a Lego Ninjago set lying around, you can totally use that with Boost too. Boost lets you build three different bases -- a walking base to create their own robot animal, a driving base for a vehicle and an entrance base for a castle or a fort. Lego calls this a "creative canvas" that encourages kids to think creatively and use their Boost bricks and coding skills with all manner of different creations.

"We know that children dream of bringing their Lego creations to life," said Kent in a statement. "Our chief ambition for Lego Boost is to fulfill that wish."