adding expenses and share them between Family members

Hello all:
am searching for an app or may be a way to share income and expenses between me and my wife,
she is using Android, and am using Ios,
what we are doing now:
we created a whatsapp group that we can type any income - expenses, but i need something that is devided to Parts to know what is where,
what things we payed, what we can avoid etc, so with this whatsapp group, i can not do any of these things.
is there away that we can share something together that has all these features?
My wife is not a tec woman, she does not love technology, so, am searching for something easy.
Thanks