People like simplicity, but behind the scenes there is a long and complex design process comprising research, insight and concept generation, iterative prototyping and design, and yet again research. Usability testing has the power to enhance the outcomes of all of the stages.

A usability test can appear very simple too – sitting a test participant in front of a prototype – paper, low- or high fidelity, or perhaps even a ready product, with a task to accomplish. But observing the interaction and examining the cognitive process is very revealing.

Good UX Designers don’t keep themselves inside the “design comfort zone” preparing products that face ideal scenarios only. Instead, their apps respond to all types of unforeseen situations. With at least 5 test participants for each design persona, they find the majority of usability problems – so that they can design better products that people love using.

After all, UX is the sum of all parts working coherently and harmoniously, in varying circumstances. Hire me and I will prepare your app for reality. My usability tests will separate a mediocre user experience from a truly good one.

User feedback session at Community Christmas Event by Smartline, 2018

“Paula is definitely one of the smartest people I’ve met. Very analytical and precise mind, in conjunction with hard work and responsibility makes it an ideal member of any team. It does not matter what job she takes, the end result is always very good. Paula has a rare feature – a constant thirst for knowledge and skills.”

Dawid Makowski, CTO


Duesday provides an all-in-one payment solution for businesses and their customers. The customer facing app, codenamed ‘Bill Freedom’, offers clear and transparent billing. Users can view, pay, and manage their direct debits on the go, expanding the potential of a traditional, and rigid, direct debit.

The main challenge of launching a new app, however, is its perceived safety. Especially, in the context of payments, new brands, and tools designed for a behaviour change. This is something that a series of surveys and usability tests across all of our design personas has confirmed.

Our app prototype didn’t feel secure to the degree we desired among our test participants. Where 0 stood for ‘it didn’t feel secure at all’ and 10 stood for ‘it felt very secure’, the app received only 6.6 out of 10. And although overall user experience and clarity of information scored high – over 8 out of 10, after a series of earlier refinements – and it was given an app store rating of 4.1 out of 5, the perceived trust remained low. The question ‘How did you feel about sharing your personal details?’ scored 5.7 out of 10, where 0 was a point of reference for a ‘very uncomfortable’ experience.

In addition, the results included statements such as “I like the context but to me it’s not telling me that it’s safe” and “It’s ok but I still don’t trust it.” The majority of users, and particularly those in older age groups, victims of scams, those with a history of mental health problems, and those working in tech, didn’t feel the app was safe enough to comfortably provide all of their personal details. Also, the app wasn’t explaining clearly enough why certain details were needed and that, in fact, they might protect the user from fraud.

The notes from our test assistants continued – “[User] feels a bit uncomfortable about DOB – someone could take it. Needs something to explain why they [Duesday] need this information. Worried that giving DOB could lead to identity theft.”, “Always uses PayPal because it seems secure. Duesday ‘doesn’t have a lock on it’.”

These notes and observations surprised us, because we felt everything was described well within the app. However, we discovered it was not described in the right places or in the most consolidated ways, and a feeling of security was not triggered by visual elements. Some test participants “concentrated hard on the privacy and security screen” to give themselves extra reassurance and proceed with the payment setup process.

This was in contrast with our desired messaging. We had to set the scene differently. Through design and microcopy alone, we wanted our users to be aware of our values and that we wanted the app to be the best it can be in their interest. Duesday was a reliable company, had bank-grade security, and was FCA licensed and regulated like British banks.

If the mission of our app was to give our users freedom and control, so they could be more on top of their recurring bills than ever, it was crucial that using the app provided this experience.

More details, including how I led my team to solve this design problem, are available upon request.

ROLEUsability Testing Lead
CLIENTDuesday, 2017-2020