I talked to some charities who work with poor people and help them with food and budgeting.
At the moment Monzo needs a smart phone to work, and not every poor person has one, yet.
I wonder whether it would be possible to give almost the whole Monzo experience via SMS and the occasionally use of a public library computer?
(Another way might be to go the way of early WhatsApp, and make sure to have a basic app that works on Java enabled feature phones, but I’m afraid that’s way too much hassle to be commercially viable at all. Even my suggestion above probably already borders on charity.)