Much of the basis for James Clear’s Atomic Habits is based on and references BJ Fogg’s research at Stanford.

As I see it, James forked Tiny Habits to make it more marketable and has had great success selling books and courses under the Atomic Habits brand.

BJ opted to provide his Tiny Habits materials and 5 day course for free as it generated more data points to support his research.

Having now read both books, I certainly appreciate the plain spoken / matter of fact style of Tiny Habits compared to Atomic Habits which felt more hyped.

Atomic Habits is interesting.

Tiny Habits is great. It is deep while being approachable. BJ Fogg is not only a serious researcher, but also a superb teacher.

Tiny Habits is a book to buy, to read, and to apply to your life (both personal and professional).

If you are serious about improvement, it is essential.

Probably. One simple habit is just getting out of the bed and saying "Today is going to be a great day!"

I haven't read the book but I posted mainly because I found the behavior model useful.