Just wanted to give you an idea for a new functionality.
The idea in a nutshell is either integrate with Spiltwise or have a Spiltwise-like functionality, with the extra of settling the debts to friends without effort.
The point is to be able to register shared expenses (imagine holidays with friends) and have a place to keep track and simplify the settling (if A owes B and B owes C, then A owes C).
Spiltwise does an amazing job at this. However, there is no automatic way to transfer the funds to friends. That is where Revolut could step in and with a click of a button allow users to pay their debts.
Hope you find this suggestion helpful.