D100

The challenge

Fitness apps are abandoned in week two because progress stops being visible, and a hundred day finish line feels theoretical on day nine.

What we built

• A single health grade the user can watch move, with today's challenge front and centre.
• Month calendar, day counter and weekly completion bars so the distance to the finish is always small.
• Achievements that reward habits like sleep and early training, and a deliberate stop flow that shows what is lost.