

what in the world?! Why would you choose to cram spheres and rectangles into a multi-click option at the top, and use the entire right-hand pane for a massive library of completed models? Is this a design tool or merely a front end for Thingiverse? Very weird design choices here.

Very useful! In 123D Design, the primitives are jammed into an option in the top toolbar, while the right-hand pane includes a whole bunch of highly specialized finished models and model parts: Battleship, Bicycle, "Gadget" which features custom-made cases for the Galaxy III and iPhone 5. * In TinkerCad, the right-side pane features a hierarchy of drawing primitives - not just basic primitives, but community-generated tools that enable parameterized shapes: not just a cylinder, but a cylinder with a top radius (x) and a bottom radius (y) and a radial segmentation of (z). I don't even know how it works yet, but it's very different, and more cumbersome, than TinkerCad's model. In 123D Design, selecting a model simply selects the model - you then have to choose Scale from the pop-up toolbar, and use the UI of the tool to scale the model. * In TinkerCad, selecting a model immediately shows a bunch of handles that you can drag to move or resize it. In 123D Design, F is merely Fit: it zooms in on the model, but apparently doesn't lock the focal point. Very soon after focusing on an object, you're no longer focused on it you're instead focused on some completely random point in space. Very frustrating. * In TinkerCad, F is Focus: selecting a model and pressing F locks the viewpoint focus on the model, and rotating the camera orbits the model. * In TinkerCad, mouse movement rotates the viewpoint, and Shift + mouse movement pans the camera. In 123D Design, holding down Shift does nothing mouse movement still rotates the viewpoint.

The biggest problem I'm seeing so far is that while 123D Design has all of TinkerCad's functionality, the UI is quite different. is stability a significant problem?), so that's off-putting, but otherwise it was OK. The app crashed once about five minutes in (er. Having spent about ten minutes with 123D Design - so far, I like what I see. I've been using TinkerCad heavily for a few months, and today I decided to give 123D Design a shot - specifically because the UI looks very similar to TinkerCad, just taken to the next level.
