Mobile web redesign, driving a +4% conversion rate uplift while reducing delivery time by half
ROLE
Senior UX Designer
CONVERSION RATE
4%
TEAM NUMBER
+15
TIMELINE
3 months
Flix is a global travel-tech company headquartered in Munich, operating FlixBus and FlixTrain networks across more than 40 countries on four continents. Known for its affordable long-distance mobility model, Flix carried 81 million passengers in 2023 to over 5,600 destinations, generating €2 billion in revenue with €104 million in adjusted EBITDA. Powered by an asset-light partnership model and a workforce of over 5,500 employees and partners, Flix has become one of the world’s fastest-growing players in modern, sustainable intercity travel.
Design Challenge
As Flix continues to scale its global mobility platform and reach millions of travelers worldwide, optimizing digital touchpoints becomes increasingly critical to sustaining growth. Despite strong traffic, our data shows a clear opportunity on mobile: mobile web drives 27M visits per month (67% of total traffic), yet converts at only 6% compared to 14% on desktop. A 1% lift in mobile CVR alone would translate into 3.2M additional converted customers annually. This insight prompted a deep dive into our mobile web experience to better understand the current challenges and opportunities.
Mobile Web UX
Is it mobile-web optmized?
Users behavior
Do we understand users’
expectation and behavior
when using mobile when
shopping online?
Performance
Are we fast enough
not to let people
abandon our site?
The Design Process
Collected insights from existing research repository of 50+ feedback from users.
01
User Research
and Testing
Organization and facilitation of two Design Sprints with cross-functional teams.
02
Design Sprint and test
Ran a big-bang, without A/B Test to measure the impact of the proposed solutions.
03
Measure the impact
01
User Research and Testing
From a series of usability testing and interviews with +50 customers, we gathered patterns of frictions on Search and Check Out funnel
The search mask, search result, and checkout flow are the main user acquisition funnels that the team is focusing on removing frictions and driving conversions. We started by profiling our customers' travel behavior and intention from our market research data. We found the two most significant profiles: Travel to visit relatives and Travel for holidays (short and long day trips).
Paul — Traveling to Visit Family
Meet Paul, one of our representative customers. Paul lives and works in Berlin and regularly travels to visit family and friends in Hamburg and Hanover, typically at least twice a year using FlixBus. His travel behavior reflects that of 48% of our customer base in Germany who use Flix for visiting relatives and close connections.
In this example, Paul is on his daily subway commute from the office to home. During the ride, he decides to browse upcoming FlixBus connections for a spontaneous trip to Hamburg. Since he prefers not to download mobile apps due to limited data capacity, he goes directly to the FlixBus mobile website to explore his options.
Anna — Traveling for Holidays and Leisure
Anna, a student from the United States, recently moved to Hanover for her studies. She represents the millennial customer segment, which makes up 38% of FlixBus users in Germany who rely on Flix for holiday travel, including short getaways, long-distance trips, or day excursions.
Planning her first trip with Flix after receiving a recommendation from a friend, Anna explores travel options from Hanover to Stuttgart—where she hopes to attend a concert and spend a few days sightseeing. Aware that Flix also offers FlixTrain connections, she compares both bus and train options on the website and evaluates which mode provides the best combination of price, convenience, and overall value.
02
Design Sprint Workshop
The Design Sprints resulted in tested prototypes to build, test and launch
2.1 The situation of Design Sprint with the product team
design sprints were conducted with two teams in total two weeks
Over the course of two weeks, we conducted design sprints with two cross-functional teams. Together, we aligned on key user frictions, co-created solution concepts, built prototypes, and tested them with users. By the end of the sprint, we had tangible, validated outputs that were ready for development and future rollout. This approach introduced a new way of working for the teams and ultimately accelerated delivery—cutting time to solution by nearly half.
Below is a summary of the primary frictions we identified (before, left) and the corresponding solutions created during the sprint (after, right):
2.2 Search Mask: Friction around entry fields and trip setup →
Proposed solution integrating geolocation and intelligent pre-selected trip suggestions.
2.3 Search Results Page: Lack of clarity in directions and travel information →
Proposed solution with clearer travel details supported by a map view.
2.4 Checkout Page: Multi-step, fragmented purchase flow →
Proposed solution with a streamlined one-page checkout including trip summary and progress indicators.
2.5 Usability Testing: Conducted with active involvement from Product Managers, Engineers, Designers, Data Analysts, and Agile Coaches.
Participatory design was at the core of this process. By involving product team members directly in the research, ideation, and testing activities, we ensured a more immersive and collaborative experience. This not only strengthened alignment but also empowered teams to make informed, user-centered decisions throughout the product development cycle.
03
Measure the impact
Design Experiments at Scale: What drove progress and what didn't
Geolocation on search mask
- 10%
Progression and CVR esp. On mobile
The first geolocation service implementation was delaying page load by 1.5 seconds. Probably too much for our users. We decided not to roll it out for now.
More advanced search result page
+13% Progression rate
-3% Conversion rate
Despite the positive progression rate uplift, we have decided not to roll out the new results for now due to a decrease in the conversion rate. Instead, we plan to make changes to the map view design.
a single-page check out
+4% Conversion Rate
13 Million new passengers converted every year
We tested the new single page checkout with clear indication of progress and this worked out really well.
Data-driven design experimentation and a user-centric process were at the heart of this project. Every decision was grounded in real user feedback and driven by our ambition to improve the mobile web experience, our highest-traffic yet lowest-converting channel with significant untapped potential. This initiative also marked the first introduction of the Design Sprint framework to our product teams, and it was extremely well-received. Since then, more teams have begun adopting design sprints in their product development workflows, especially for projects that require rapid innovation and cross-functional alignment.
This section captures the key outcomes and learnings from the project, showcasing how a user-led, experiment-driven approach can meaningfully shape product direction and unlock measurable impact.