Physion vs. Algodoo
If you've used Algodoo, you already know why it has such a loyal following: it's a genuinely good 2D physics sandbox with a long history, a huge community, and some features (optics especially) that go deeper than most alternatives. If you're reading this, there's a good chance you searched for something like "algodoo alternative," "algodoo online," or "algodoo no download," which usually means one specific thing: you want to skip installing anything and just start building.
That's the honest, direct comparison this post is trying to be. Physion and Algodoo solve a lot of the same problem, drawing shapes, connecting them with joints and springs, watching physics happen, but they make different tradeoffs. We'll cover both fairly: what each one does well, where Algodoo is still ahead, and where Physion's browser-first design changes the equation.
