A trip abroad
An example, with sample figures.
Five friends, a week away, and only you have the app.

You make a group and name everyone, so nobody else needs the app. Each cost is shared equally as it's recorded.
At the end you send the summary to the group chat, and record each payment as it's made.
Worth knowing
It records payments and never makes them. Each currency stands on its own row, and nothing converts between them.
Share a cost