The method came before the product.
On Vocation was published by Routledge years before there was an app. Everything the product does can be traced back to it, which means it can also be argued with.
Gallup puts disengagement at work at eighty five percent. On Vocation was written as a response to that number, and it makes one claim the whole product now rests on.
Purpose is not found. It is built.
The books are guides for individuals and for the organisations they work in, aligning passion, purpose and profession. They function as a mirror rather than a manual: they do not tell you what to do, they make you answer.
Also available on Amazon and Apple Books.
Why a book matters here
Most career products start with a feature and reverse engineer a philosophy. This one started with a published method, which is what makes the product falsifiable: every question the app asks traces back to a written argument, and that argument can be disagreed with.
It also sets the boundary. The method says you cannot think your way to a direction, only act your way to one. That is why the product makes you send something real to a real person, rather than scoring your personality and handing you a report.