Mobile app for selling and buying pre-owned clothes

How many pairs of shoes do you have? How many t-shirts? How about pairs of jeans? Now get up and count them. You’ll probably be surprised by how underestimated your guesses were.

The truth is, almost everybody owns clothes that are no longer worn for various reasons: they’re out of fashion, they don’t fit, or we simply have a couple of favorite outfits that we wear more often than anything else. At the same time, we feel a crying need for staying fashion-forward. Is this goal even attainable without causing your closet to burst and your bank account to be frozen?

Even if you’re tempted to answer yes immediately, think twice. Reports say that the apparel and footwear industries generate over 8% of global pollution impacts. The total greenhouse gas emission produced by these two sectors reaches 1.2 billion tons every year. What do these numbers mean in practice? Fast fashion is killing the only planet we have.

But fear not, eco-conscious fashionistas, we’ve developed a solution that will help you stay trendy and protect the Earth. That’s a mobile app for selling and buying pre-owned clothes called LESS_


Frontend DevelopmentBackend DevelopmentQuality AssuranceUI/UX DesignProduct & Marketing StrategyBranding


React Native + Firebase + Visual Studio App Center + Python + Django + Celery + RabbitMQ + Google Cloud Platform + Kubernetes

How it all began - Count Me

The story of LESS_ begins in 2014, long before Apptension became involved in the project. Back then, Mateusz Oleksiuk dreamt up an app that would help people get shopping under control.

The primary version of the app, known as CountMe, enabled users to create a virtual showcase of their buys (including clothes, cosmetics, and all sorts of gadgets) as well as travel destinations.

CountMe played a dual role back then. One the one hand, by recording the prices of goods at the time of purchase, its users could manage finances better. On the other hand, by giving people a chance to rank in the top 10 shoppers or globetrotters, the app boosted their self-esteem and fostered the sense of community.

Being aware of his own limitations, Mateusz Oleksiuk started seeking financial help that would enable CountMe to reach its full potential. His pitch caught the attention of Dawid Urban, the Polish business angel who’s already supported dozens of innovative startups. Having provided software development services for one of his investments, Adquesto, we became an obvious choice for CountMe’s tech partner.

A brand is born - LESS_

Mateusz Oleksiuk approached us with innumerable ideas for revamping CountMe which is why our collaboration started with a client-team workshop. As part of the discovery phase, we identified business goals, delineated primary functionalities, and brainstormed relevant tech solutions. The result? A viable plan for building an app with the potential to revolutionize the Polish second-hand apparel market.

Once we reached an agreement on the project scope, our Creative Team stepped in and asked the following questions: What does the product stand for? What value does it offer its users? To answer them, we analyzed the hard data as well as consumer behaviors of young adults, both of which brought us to the following conclusions:

  1. You can have too much of a good thing. The bigger our closets get, the more time we spend arranging them and working to afford them. The more clothes we own, the more time we spend choosing the perfect outfit, which often leaves us dejected. On top of that, research says that no matter how many pieces of clothing we own, at the end of the day we wear no more than 50% of them. Cutting back on the available apparel choices, on the other hand, simplifies decision-making and results in greater peace of mind.

  2. Our fashion choices are well-thought-out and purposeful. We know that it’s the quality not quantity that matters, which causes us to buy apparel made of more expensive yet longer-lasting materials. Today’s consumers are also aware of the fact that nothing expresses their fashion sense better than a few carefully selected wardrobe staples and statement pieces. For that reason, they give up on binge shopping in chain stores. In the words of Vivienne Westwood, we now buy Less, choose well, and make it last.

  3. Fashion choices we make influence our surroundings. According to the ThreadUp report, we use 108 million tons of non-renewable resources a year to produce clothing. At the same time, the equivalent of a garbage truck of textiles is burned up every second. Since we’re buying twice as much and wearing it half as long as we used to in the early 2000s, we’re in desperate need of ethical and sustainable fashion solutions.

When Apptension became involved in the project, the app, which primarily served to showcase all goods we proudly possess, did a 180-degree turn. CountMe was transformed into LESS_

The new name speaks for itself: the app has become a tool for change towards less stuff and less waste. It allows users to keep upgrading their style while simultaneously supporting sustainable lifestyle and reducing textile waste. As compared to CountMe, it puts greater emphasis on responsible shopping and eco-friendliness. Awareness, style, thrift - in terms of brand philosophy, there’s nothing more an informed user could ask for.

How it works

The buying and selling process taking place in LESS_ is pretty straightforward. It all begins with a seller taking quality pictures of clothes or accessories to whom they wish to give a new life as well as choosing the type of offer they’re interested in: auction or buy now. Once a buyer expresses interest in purchasing a given item, the two get in touch to discuss payment and shipping method.

Nonetheless, LESS_ is not only about selling and buying. The app offers a social component as well. Users who are into showcasing their fashion sense do so by adding photographs of outfits together with information about the products’ brand and price to a virtual closet. Every new addition can be liked and commented by the original poster’s followers.

The tech

Let’s start with backend which breathes life into software while staying invisible to the client or the user. In case of LESS_, it takes care of the entire business logic, including arranging feed, displaying posts, searching, adding to favorites, bidding, and buying.

With code written in Python, Django was an obvious framework choice for us. Since its introduction to the market in 2005, the framework has become a reliable solution supported by a large developer community. Containing a number of additional functionalities, such as an admin panel, mitigation for cross-site request forgery, and tools for creating database schemas, Django allows developers to focus on business logic and simply makes backend development more efficient.

To ensure smooth and faultless execution of all tasks within the app, we went for Celery and RabbitMQ. This solution makes it possible to execute the tasks asynchronously and repeat them in case of failure such as an unsuccessful delivery of email. Moreover, the ease of Celery - Django integration facilitates the overall development process and allows for faster project delivery.

Targeting LESS_ primarily at young social media users, we had to stand up to the challenge of preparing the app for traffic peaks induced by influencer marketing campaigns. We determined which points will be most susceptible to high traffic and conducted stress tests. At that point, we knew that when the need for new resources arises, a new cloud instance deploy will have to take place fast. In simpler words, we wanted to ensure maximum efficiency while keeping running costs to a minimum. __That’s why we used Google Cloud Storage, Kubernetes, and Firebase for storage, scaling, and analytics respectively. __

Last but not least, making safety of LESS_ users a top priority, we implemented Auth0 for authentication and authorization.

The second pillar of our work at LESS_ was frontend development, which involved building all elements of the app’s interface and integrating it with backend. Our priorities in this regard were optimizing user experience and ensuring top performance on all, even slower, devices. Tech stack used for that purpose included React Native, Firebase, and Visual Studio App Center.

Firstly, since LESS_ was supposed to run on both Android and iOS, we choose the money and time-saving path of React Native. Based on Javascript and React, the Facebook-created framework uses a set of platform-agnostic native components, which account for truly native UI and seamless user experience on both platforms. Another advantage of using React Native for us is that it simply holds no secret for our developers.

Secondly, Google’s Firebase facilitated our work with a couple of functionalities: collecting statistical data on the app and its users’ behaviors (Firebase Analytics), sending notifications (Firebase Cloud Messaging), facilitating communication between users with a chat (Firebase Cloud Firestore) as well as sending and downloading files in the easiest way possible (Firebase Storage). A major pros of Firebase for us is that being backed by Google, it’s stable and reliable.

Finally, Visual Studio App Center allowed us to automate development and testing of the app in the cloud, as well as efficiently distribute the application to iTunes Connect and Google Play Console.

Capturing users’ attention

The rebranding choices were dictated not only by the current trends but also by the app’s target audience. Being a resale tool, LESS_ aims to attract attention of two types of users: buyers and sellers. We defined the former as the young fashion freaks and bargain hunters, and the latter as fashionistas and influencers who seek to breathe fresh air into their closet while simultaneously inspiring their followers to support sustainable fashion.

Having in mind the target group of tech-savvy millennials as well as the brand’s preoccupation with the well-being of the Earth, our Creative Team came up with an idea for an intriguing teaser campaign. It all started with a group of influencers who support the philosophy behind LESS_, including Weronika Sowa, Radek Pestka, and Fit Lovers. To awaken their followers’ interest, celebrities posted pictures of themselves holding mysterious numbers. The question was, what do these numbers mean?

Commenters’ guesses ranged from the number of relationships to the amount of money they make on Instagram. The truth was revealed a couple days later: the numbers stood for the pieces of clothing which influencers own but do not wear. The disclosure post was illustrated with a photo of the celebrity wearing an outfit that can be bought in LESS_

Backed up by the engaging introductory campaign, LESS_ quickly became a notable success. Within only 3 days from the release date, the app was downloaded 14k times and secured the first place in App Store Shopping Apps ranking.

What's next

Being a fully-fledged tech partner and business consultant to the client, Apptension remains involved in developing LESS_. We’re researching users’ needs, implementing new solutions, and making sure the brand communication in heading the right direction. As we’re writing this case study, the Polish LESS_ community is steadily growing. Next stop? Europe, and then the whole world!


Tech Lead
Michał Kleszcz
Frontend Developer
Marcin Bazanowski
Frontend Developer
Martin Kmieciak
Frontend Developer
Jakub Matyśkiewicz
Frontend Developer
Jakub Wiśniewski
Backend Developer
Krystian Hanek
Junior Backend Developer
Filip Wolwowicz
QA Specialist
Olga Kamińska
QA Specialist
Dorota Zabielska
Creative Treatment
Zbigniew Czarnecki
Product & Marketing Strategy, Creative Treatment
Michał Gutkowski
Art Director
Agnieszka Czarnecka
UI/UX Designer
Magdalena Seget
UI/UX Designer
Mateusz Sówka
Project Manager
Maciej Korpik
Project Manager
Aleksandra Leończyk
Project Manager
Jakub Stachowiak
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