One workbench for the whole craft: your formulas with real version history, your material shelf, what ingredients actually cost across different shops, and a way to swap surplus and buy in bulk together. No more juggling Excel, notebooks and a dozen browser tabs.
The everyday stuff, in plain terms.
It's a proper workspace for building a formula, with every layer, ingredient and concentration in front of you and cost updating as you go. The kind of thing you keep open while you actually mix.
Free, no invite needed, just a handle and a password and you're in. It works on phone and tablet, but the bench really opens up on a laptop or desktop.