Hello.
Sometimes it comes in handy to be able to make basic calculations to out money(ie: sum the total of one day's worth of food expenses, before i add it as an expense).
Having to access an external calculator in some cases requires us to close the app.
It would be a great addition to be have a icon/something to access a simple calculator (ex: popup dialog).
I would assume it takes a little efford to implement this, improving to the user experience.