I basically used the no-code environment of Bubble.io to see, if you can really build a proper SaaS product with it. While the editor is extremely lackluster and doesn't allow for responsive design like e.g. Webflow, I was blown away by the feature-rich workflow-engine.
With a lot of trial-and-error I built a drag-and-droppable interface for lean canvasses and added two very in-depth sections that walk you through the ideation and problem interview phase in the style of "Running Lean" by Ash Maurya.
It was a blast to build and I was able to incorporate it into my ELP (http://austrianstartups.com/elp/) workshops and use it in a few consulting gigs.
I'm quite certain that with a bit of polish this could be turned into a small but helpful productivity tool. But for now, it's a free ultra-alpha no-code showcase that you can play with.
I'm available for consulting gigs, software development, interviews and long term involvement.