How do mobile money payments work in an app?

Mobile money in an app works like this. The customer enters their mobile money number. A prompt appears on their phone asking them to approve the payment with their PIN. They approve, and the app is told the money has moved. No card, no bank account.

That's the happy path. The build is everything around it.

Why does it matter so much?

Because in a lot of countries more people have a mobile money wallet than a bank card. In Ghana that means MTN MoMo, Telecel Cash and AT Money. An app that only takes cards has locked out most of its customers before they start.

Do you connect to each network yourself?

You can, and you shouldn't for a first version. Each network has its own process, paperwork and technical connection.

A payment provider gives you all of them through one connection, usually with cards as well. Paystack, Flutterwave and Hubtel all do this in Ghana. You pay a percentage of each payment for it. Paystack's published rate for mobile money in Ghana is 1.95 percent.

The provider will ask for a registered business and its documents before you can take live payments. Start that early. It takes longer than the code.

What makes it harder than card payments?

Waiting. A card payment says yes or no in a couple of seconds. A mobile money payment waits for a person to pick up their phone and type a PIN.

So the app has to handle the in-between.

• The customer never sees the prompt, because of a bad signal.
• They see it and ignore it.
• They approve it, but the confirmation reaches the app late.
• They try again because nothing seemed to happen.

Every one of those needs an answer on screen. A spinner that turns forever is how you lose the sale and get the angry phone call.

How should the app handle a slow payment?

Show a clear waiting screen that says check your phone and approve. Give it a time limit. If nothing comes back, don't guess. Ask the provider what happened to that payment before you tell the customer anything.

And never trust the phone alone. The app on the customer's phone can say paid when it wasn't. The provider tells your server directly, and your server decides.

What about paying people out?

If your app pays drivers, sellers or agents, money has to go the other way too. Most providers can send to a mobile money wallet.

Decide the rules before you build: how often, what minimum, who covers the fee, what happens when a number is wrong. Payouts are where a platform earns trust or loses it.

How do you keep the books straight?

Every payment gets a reference of its own, and every night what the provider says you received is checked against what your system says. The differences are small and they are always there. Somebody has to look at them.

We run card payments and subscriptions in our own products. Mobile money is the same discipline with one extra state in the middle: waiting for a person. Design for that state and the rest follows.

What should you decide before the build starts?

1. 01Which networks and which provider.
2. 02Who pays the fee: you or the customer.
3. 03What the customer sees while they wait, and for how long.
4. 04How refunds work.
5. 05How and when you pay people out.

If your app also takes cash, that's a design of its own. I covered it in how to build a ride-hailing app in Ghana. If you want payments built properly into an app, that's what we do. Tell me what it has to do.