Picture: ISTOCK
Picture: ISTOCK

Stingy people are intolerable. Doing anything with them is painful, and not just because you have to shell out to cover their drinks, meal or portion of the tip (they're much too miserly to tip appropriately). The dreaded penny pinching kills the mood.

Flaky people aren't easy either. They can be just as expensive as stingy people, but for different reasons. They don't have a clue. Life's a cabaret and they often forget to pay.

Proud people can also be tricky. Sometimes pride masquerades as generosity. Before you've even asked for the bill, they've settled it. They have trouble letting you pay your way, and can't receive from others. You feel constantly indebted to them.

The truth is we're all pretty rubbish with money. Because we're people. But we're even worse when it comes to doing money with others, says Christo Davel, the co-founder of money management app 22Seven. "And that's the worst for relationships."

Since leaving 22Seven, Davel and Dennis Williams, who was also part of the 22Seven team, have developed an app that ambitiously aims to "solve a problem as old as people and money: people and money".

It's their hope that by using Kin you won't lose friends over money, or money over friends.

Kin enables you to create a joint record with select friends or family members around specific collaborations (called kins) involving money. A kin can be as simple as a coffee club for colleagues or something more complex, such as siblings supporting parents.

The app enables all the members of a kin to track shared expenses, get paid what is due to you and pay anyone who is owed money by you.

You can upload invoices, bills and till slips and set the percentage split.

The app keeps a running total of who owes and who is owed, and when an expense is loaded, everyone gets a notification.

All users can upload any bank card details of an account from which they would like to pay and banking details of an account that they want to receive money into, which you do just once.

Having been in a testing phase for eight months and on the market for only one month, Kin is being used mostly by people in shared living arrangements, by people taking weekend breaks together, by co-workers and a few small businesses. It's proving popular with divorced couples.

Williams says the benefit for couples who've split up, especially those with children, is that "it becomes a safe space where they don't need to talk". There are school fees and other regular shared expenses that have to be paid. These get loaded on the app and the other party is notified.

While the app may be useful to stokvels, Davel says it's not competing with Stokfella (which is all about the ledger), and it wasn't developed with stokvels in mind. Kin's focus is far broader.

He says Kin is "like WhatsApp for money" because setting up a kin is as easy as starting a WhatsApp group, and kins are like closed social media groups involving money.

The group dynamic is at the heart of Kin.

Both Davel and Williams saw their own behaviour change in a radically positive way when they were part of the team that developed 22Seven.

"We were obsessed with behavioural science," says Davel. "We found that just being exposed to the thinking, we all ended up with less debt or more money to spend."

Williams tells of how he used to be "bad with money". But soon after joining 22Seven he met someone who had done the sums and found that it made more sense to sell his car and to use Uber instead. "I did the maths and sold my car. I could have read that, but nothing is as powerful as the people you work with. It's the constant filtering."

Davel says that when they left 22Seven, they had the sense that their work was unfinished. "We thought 22Seven would help people be smarter with money if they saw the big picture." But instead of reaching a mass market, it appealed mostly to people who were already good with money.

"When we stopped to look at what had changed [over time], the connecting socially, forming groups on WhatsApp, sharing and doing stuff together had increased dramatically. Relationships are complex already. Add money and it's more complex," Davel says.

Getting people to be better with money is about changing behaviour, or learning how to change behaviour, Williams says.

"We know you learn better from seeing what other people do and from getting validation when you do something right. The trigger in the learning is when it's validated," he says.

For this reason, the next version of the app will include "likes", which are a popular way for social media users to give validation.

"We believe that if we create these little networks, quickly we will be able to see from the data what works and what doesn't," says Williams. "So, if people in house shares show certain behaviours that work better, we can work that into the product. For example, if you agree on certain things upfront, or pay before a certain date, or make certain payments automated, we can see the cause and effect and give that value back. Because we're learning from the network.

"On top of that we've got aspirations of building it out so you can see what we can learn from how random people go on a trip to Portugal, for example, or go away for a weekend." The idea being to learn from other groups such as yours.

By connecting and learning from others, it speeds up the learning process.

You can download the Kin app from the Apple Store or Google Play.