Wells Fargo quietly rolled out its Daily Challenge app late last year, inviting customers to take on things such as brown-bagging their lunch for a week.

Users receive push notifications telling them to transfer the money saved during the challenge to their savings account. Each transfer earns a check mark on the Challenge progress bar until it is completed and a congratulatory message is received.

The app also lets customers set their own savings goals, providing details of how to reach them and using push notifications to show progress.

Jonathan Hartsell, Wells Fargo financial health programme, says: "We’re always looking for innovative ways to use digital to help our customers build good financial habits. Having an app focused on helping customers build their savings will allow them to take action and see the rewards. The hope is that by completing simple, fun savings challenges, it will become a habit that sets them up for financial success."

Meanwhile, PFM specialist Meniga is preparing to launch its own Challenges module. Similar to the Wells Fargo app, Meniga's tool has options such as 'no fast food week' and one-offs such as 'the chopping block' which shows users their subscriptions so that they can unsubscribe from redundant ones.

A Meniga Money Monster even "steals" variable, random amounts from a user’s current account and puts it into savings.

Meniga, which counts Santander, ING and Commerzbank among its clients, says that the likes of PSD2 means that banks are being forced to innovate to maintain strong relationships with their customers.

Finnur Magnússon, chief product owner, says: "By combining social online fun with techniques that drive positive daily lifestyle changes, we applied an approach to finance already proven in other areas like health. Small everyday changes can make a huge impact on the customer’s long term saving and spending pattern."