Business banking app

Thinslices' Journey with Penta in the European Fintech Landscape

Based in Berlin, Penta started its journey in 2017, and has been Germany's leading provider of digital financial management for SMEs, self-employed and freelancers. The end goal of Penta was to create an integrated digital banking platform that brings together the best of financial services integrations, so that their users can effectively manage all their business activities from the same application. Starting from simple payments to accounting activities and credit management, Penta’s end-users have benefited from features like: expense management and international payments, direct debits and batch payments, customized user management and Visa cards, integration with the desired accounting software.

Being one of the most significant up and running German fintechs with more than 50k users, Penta was acquired by Qonto in July 2022. The two market leaders aim to generate added value for their customers through further innovation in their products and services within the European market, especially in Germany, France, Italy and Spain.

Thinslices started its collaboration with Penta back in 2020, in the middle of the pandemic, when Penta reached out to us to help them build the mobile version for their digital banking application.


The challenge

How can we build a mobile banking app that would be in parity with the existing web version and give users a sleek and easily accessible platform for everyday use, in a short period of time?

Our approach

Penta’s goal was to develop a mobile app that would complement their existing web platform whilst hitting tight deadlines for market release. After defining the scope, ways of working and the desired product roadmap, we’ve rapidly put together a team of 7 engineers, one UX/UIdesigner and a product manager who were able to quickly start the onboarding process and jump straight into delivery.

For nearly 16 months, our team’s main focus was to bring a mobile app to parity with the web version, in order to allow Penta's new and existing users to enjoy from the comfort of their smartphone, the majority of features already existent on the web platform.

Following a first, major and successful release of onboarding new users (sole proprietors and freelancers) in Jan 2021, our team has worked together with Penta to define the next steps of the product roadmap; and we’ve started working to add Sub-Accounts and Permissions features to the mobile app, which facilitated users to organize their business finances under a single account. This second phase of the project was completed before the end of 2021.

During the entire collaboration with Penta, the Thinslices team worked mostly autonomously on all the tasks. We have rapidly integrated with Penta’s product development process, and always strived to deliver on the immediate needs whilst identifying key blockers. Our best practices and delivery methodologies have been recognised and appreciated within Penta’s teams, which led to an ongoing successful and trustworthy partnership.

Post the acquisition by Qonto, our team was asked by Penta to help with the migration of all of their users towards Qonto, and help with the sun setting of the platform, which is scheduled to be completed by the end of 2023.


2k +

mobile users on boarded across iOS & Android


OKRs accomplished


Android customer ratings (Increased from 3.9)


iOS customer ratings (Increased from 3.7)

Technical specifications

React Native, ObjectiveC/Swift, Java/Kotlin
Google FCM & Big Query
Bitrise & Fastlane for deployment
& Sentry for issues tracking
AppsFlyer & Snowplow integrations for marketing and data teams

Delivery Process


0 Blocked days

% Blocked days = percentage of days, in a sprint, when a feature delivery was blocked.

0 Delayed days

% Delayed day = percentage of days, in a sprint, when a feature delivery was delayed.

0.5 - 1 day test days

AVG Days to test and close = days required for sign-off and ship. (depending on the complexity)

2h MR closing time

AVG MR closing time = number of hours required for review and merge with common code.

6SP per developer

AVG SP per developer = average number of story points delivered per developer per sprint.
Our work

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