We grew up watching our parents keep the Vyavahar Book.

Every Indian family has one. A worn register, sometimes a spiral notebook, held carefully by one member of the family — the uncle who remembers everything, the grandmother who never forgets a number. At every event, it comes out. Gifts are recorded in neat columns: name, amount, relation.

This is the Vyavahar Book. And it is one of the most important social contracts in Indian culture. When your cousin gets married, you look back and give exactly what her family gave at your wedding — often down to the rupee. The book is how families maintain reciprocity across decades.

But the paper book has limits that are becoming impossible to ignore. It lives with one person. It fades and tears. It cannot be searched. When the keeper passes, so does the knowledge. And in a world where families are spread across cities and countries, the cash-in-envelope model no longer works.

Nyutabook was built to honour the tradition and fix the tool. Not a payments app. Not a gift registry. A lifetime family ledger — digital, searchable, permanent, shareable.