The Achilles heel of this inspired LEGO STAR WARS BOOST DROID COMMANDER CODING STEM SET (75253; New 2019, 1177 Pieces) is the app. The set does NOT include printed instructions--and printable instructions are NOT available from the online LEGO Shop--so you MUST build the three robots with the app’s building instructions.Although I’ve assembled dozens of complex LEGO sets, I struggled just to get the basic robots built. The app requires you to build the robots in a strict order (R2D2, Gonk, Mouse), and the app is difficult to navigate if you need to back up (e.g., to look for a build mistake, or to view the coding tutorials a second time). It can be hard to reach the Cantina projects, and it’s hard to find the motor-swapping instructions when you want them.+++Your App Choice Matters. Some of my problems were caused by the Amazon Kindle tablet app (the updated version). When I switched to the iPad app, valuable pages of extra instructions (e.g., help with ribbon cable placements, troubleshooting tips) appeared--these pages were missing or blank in the Kindle app. If you buy this set, you should probably use the Apple or Google Play app, rather than the Amazon Android app.Note also that the Move hub firmware needs updating from time to time. This happens automatically when your mobile device is connected to the Internet, and the Move hub is connected to your device via Bluetooth. So do use the app occasionally while you’re online.+++Confusing Coding Tutorials. The set is promoted as a tool for teaching coding. The coding mystified me, for two reasons. First, my 7” Kindle tablet made the visual coding blocks almost too tiny for me (or anyone) to distinguish their specific features. Second, the app’s refusal to let me back up to review the tutorials, to understand them better, left me with programming by trial and error.Before you go into the first tutorial, you should probably download and print the explanation of the Boost coding blocks that’s available in the LEGO Shop. (Go to Menu, Support, Common Questions, Products, Electronics and Robotics, Boost, Guide to Boost Programming Blocks.) The Boost blocks are a little different from the Boost Star Wars blocks, but the guide will help you understand how the programming generally works.If you need a second look at a tutorial, you can do it by invoking the robot’s “Build” instructions again, going to the end, and checking “Build Complete” again. This will then require you to complete the tutorial before proceeding, same as before.+++R2D2 Robot. When I completed the R2D2 robot, the robot woke up, and would execute a few programmed commands. However, the robot kept falling over, and the head kept coming off. I later discovered the fix--with the motor module removed, press the crankshaft underneath that secures the head while you push the head onto the top of the crankshaft. However, this is NOT something that you would think to do while you are building the robot for the first time. Until I made this change, I couldn’t get the R2D2 robot to respond to the app’s controller buttons.***GONK Robot. When I completed the Gonk (box) robot, the robot woke up, and walked several steps. However, I repeatedly got a message that the robot calibration failed. After I switched to the iPad app, I got an additional message to “check the pins”. I’ve done that, and the pins are properly installed, so I assume that there is an error in the build somewhere. I will have to take the robot apart and rebuild it, if I want to drive it with the app’s controls.+++Mouse Robot. When I completed the Mouse robot, I was able to drive it right away. However, the programming was still a mystery until I watched a YouTube video about Boost programming. This might not have been necessary if I’d been able to study the R2D2 tutorial (no repeats allowed, as previously mentioned), which includes more information about the basic steps in programming (e.g., select a visual “power” piece for the robot you’re setting up).+++General Observations. The three robots are larger than I expected (about 8.5” high). You can operate only one at a time (unless you purchase additional Move hubs, motors, and sensors). However, the Move equipment is easy to swap into and out of the robots.The app includes a lot of “missions” to be completed after you finish building the basic robots. Completing a mission unlocks more missions. You use the parts from cellophane bag #11 to build the robot saw arm and other add-ons needed for the missions. Thus the app includes many additional play activities.Kids who are learning to code in grade school will probably NOT find this set as challenging as I did. However, the set wouldn’t have been nearly so difficult if I’d started with the iPad app. It would also have been easier if there had been printed building instructions, which are easier to build from, even though they don’t have the app’s ability to rotate the model through 360 degrees when you’re unsure about where an element is supposed to go.Now that I have it working, I really love the R2D2 robot. It drives beautifully, without falling over, the head rotates all around, it plays music, and it mutters to itself. As time permits, I will go back into the app, rebuild the Gonk robot, and complete the missions. This is giftable, but it's NOT really a beginner's coding set, and it includes some fairly sophisticated LEGO building techniques.