Websites, e-shops and apps
E-shop, Website and Web Application Design and Development
Hundreds of websites, e-shops, and apps for B2B and B2C. High-performance lead-generation sites, large and mid-sized e-shops, apps that simplify work. Data-driven, no vendor lock-in.
Custom E-shops
We design, develop, and maintain large and mid-sized e-shops with annual revenue from 150M CZK. No vendor lock-in, with emphasis on performance and long-term growth.
Learn more about the service →
Lead-generation Websites
We build fast, clear, and functional websites that effectively support your sales team and marketing communication strategy.
Learn more about the service →
Web Applications and Internal Systems
We create applications that will make or speed up the work of people in your company, your customers, or yourself.
Learn more about the service →
User Research
How do customers behave on your website? What do they pay attention to? What's missing? Where are they confused? We find answers to these and other questions.
Learn more about the service →
Website and Mobile App Analytics
We set up technically and legally correct measurement of websites and apps to help you understand your users.
Learn more about the service →
UX & CRO
We design or improve your website or e-shop to meet customer needs and maximally support the purchase process.
Learn more about the service →
Template Coding
We create functional, optimised, and fast HTML templates for your designs, ready for deployment.
Learn more about the service →
Custom Development
We manage the entire development process of a new digital product, or the modernisation of an existing one.
Learn more about the service →
Design Systems
We create a design system for your application or large-scale website to accelerate development and enable easy scaling.
Learn more about the service →
Book an hour of no-commitment consultation with a strategist
A partnership that keeps Top-obaly.cz e-shop revenues growing 40% every year
For over ten years we have been continuously improving the e-shop and making it easier for its customers to shop. Our project management is guided by ongoing research, diligent backlog management, regular status calls, and annual roadmaps.
Top 10% worldwide
Top-obaly has averaged a 9% conversion rate since 2015, placing it among the top 10% of highest-performing e-shops in the world.
98% satisfaction
5 stars in overall satisfaction ratings for Top-obaly from 5,958 out of 6,187 verified Heureka.cz user reviews.
+10% user engagement
User engagement on mobile devices increased by 10%, meaning users interact more with content and stay on the site longer.
70th fastest e-shop
Among the 500 most visited e-shops in the Czech Republic, Top-obaly ranks 70th for desktop and 129th for mobile.
Less than 8 months of operating the new e-shop was enough to pay for 7,000 hours of our work
The Nazuby.cz e-shop ranked among the top 20% of highest-performing e-shops in the world before its redesign, according to metrics published by Wordstream.com. It was therefore absolutely crucial to eliminate the risks associated with replacing the old website with a new one.
+40% profit
After adjusting for natural growth and other factors, profit grew by 24% due to the redesign alone.
+27% revenue
Revenue increased by 27%. Revenue on Nazuby.cz grew by 37% and by 49% on Nazuby.eu.
+33% conversion
Average conversion rate increased by 33%. Specifically +32% on mobile and +38% on desktop.
100+ hours invested in the key B2B landing page for the Project Preparation service paid off the very next day
Context and market analysis, research with sales teams, design, development, and marketing communication strategy. The landing page generated contracts on its very first day that fully covered 100 hours of our work.
We led the digital transformation of SAPELI and designed a unique configurator with billions of door product variants
As part of the B2C and B2B digital ecosystem transformation for SAPELI, we designed one of the most sophisticated door manufacturer configurators in the world. Thanks to 70 hours of user testing, its ease of use is comparable to navigating the Instagram app.
By optimising the Artmaster course landing page, we increased revenue by 35% in 2 weeks
We redesigned and tested the course detail page — the key sales section of the Artmaster website. The changes boosted website performance and overall business results by increasing revenue by 35%.
+49% interactions
Visitors launch videos 32% more often and trailers 49% more often, click the purchase button 19% more, and register for courses 49% more frequently.
+42% conversions
Within 2 weeks, we increased the number of Artmaster courses sold by 42% through optimisation.
We reduced EG.D customer line requests by 20% and saved hundreds of thousands in operating costs
When a customer helpline acts as a guide for clients navigating the website, it means unnecessarily high costs per call. It also points to website shortcomings — in the case of EG.D, that was its complex architecture.
+48% findability
By simplifying the EG.D website structure, working consistently with navigation hubs, and optimising landing pages, we increased the success rate of finding target pages by 48%.
7× more visits
We designed a responsive version of the EG.D website that increased mobile traffic sevenfold in 2020.
+7.2% online submissions
Online form submissions increased by 7.2% compared to postal requests, saving EG.D hundreds of thousands annually.
Leads for the Entire Digital Product Creation Process
Our Proven Know-how
Optimisation? Redesign? Simpler system for partners? Digital transformation?
Let's discuss what you're currently facing
Don't want to wait? Call +420 604 122 182 or email tomas.izak@proofreason.com
Tomáš Izák
CEO
„Proof & Reason don't blindly do what the client wants. They think about the brief, keep an eye on details, and give us thoughtful feedback. They're also strong in development and planning. We always know how the project is progressing. When something goes wrong, they acknowledge their mistake. We treat each other as partners. We're truly developing the e-shop together. It's great and fair.“
Ladislav Carda
E-shop and Logistics Manager, Top-obaly.cz
„Working with Proof & Reason is like getting into a Lamborghini. Yes, they're more expensive than the competition, but their approach and especially the results of their work are absolutely top-class.“
Lukáš Pítra
Online Marketing Expert
„What I value about Proof & Reason is their approach and openness. They always met deadlines and everything was transparent. They don't keep their know-how to themselves — they transfer it to the client. I was able to expand the team's capabilities, teach many people to learn and grow. I see that as a major plus.“
Tomáš Kučera
VP Sales & Marketing, Sticky Password
(now Director of Sales, Lingea)
„A quality result can't be achieved overnight. Work on the website design took a long time, but it was worth it. The result speaks for itself.“
Jan Stejskal
CEO, Nazuby.cz
„We wanted to bring a new application to market for installation companies and solar power plant owners, so that anyone could fully harness the potential of renewable energy sources. We knew it wasn't just about the technical perspective, but also the overall design, UX, and marketing strategy. That's why we chose Proof & Reason, which focuses on the overall customer experience and can approach the topic from multiple angles.“
Michal Hrabi
COO, SOLSOL
