Brain Sumo

A 2-minute daily brain workout — stamp your calendar, help Grandma Ume's shop.

Brain Sumo is a two-minute-a-day brain-training ritual. Work through quick calculation, memory, and reflex exercises — the full roster inspired by classic brain-training games — then press a Japanese hanko stamp into your own calendar to mark the day.Every session helps Grandma Ume run her little stationery shop:• 13 playable exercises: calculations, Stroop-style color tests, mazes, memory, counting, and more, unloc…