Memento

Investigates a product or startup idea for founders. Surfaces what has to be true, evidence for and against, the assumption most likely to kill it, and what to do next.

Buckets everything into a review page you can actually read, then acts on your decisions. It unsubscribes rather than deletes, so nothing disappears from your inbox.

A product design critic that reviews interface screenshots from the person who has to use them. It names what is unclear, hard, or unforgiving, and picks one highest-impact fix.