cara care

Cara Care is a gastrointestinal health app. It helps patients with IBS, IBD, and related conditions track symptoms, nutrition, and stool patterns in a way that generates clinically meaningful data. A type of data good enough to guide treatment decisions by the medical research team behind the product.

When I joined the team, the product had grown in pieces and in different directions. Different parts had been built by different teams at different times with no shared design language. The result was an app that worked, technically, but felt incoherent, with fragmented UI, no clear brand voice, and no system that could scale.

01. No clear path to profitability. The business model depended on becoming a DiGA-approved digital health application (a German regulatory certification that makes apps prescribable by doctors and reimbursable by health insurance) Without it, the revenue ceiling was low. With it, the commercial opportunity was transformative. But the app, couldn't credibly support that application as it existed.

02. Great research, no infrastructure to capture it and apply it. The medical team had deep clinical knowledge and understood what data they needed. But the app couldn't collect it reliably. Tracking was inconsistent, unguided, and not tailored to individual diagnoses. There didn’t exist a mechanism to convert and structure the data into researchable data points.

03. No voice, cohesion or UX foundation. The product lacked a consistent visual language, tone of voice, or design system. Different screens felt like different apps. Everything needed to be systematically built from scratch.

Cara Care sits at an uncomfortable intersection: it deals with topics that are genuinely taboo (bowel habits, chronic pain, mental health linked to digestion) and users who are often anxious, frustrated, or in physical discomfort. Getting the brand tone wrong in either direction, too clinical, or too casual would break trust.

The brand needed to hold three qualities: safe, no taboo (sensitive towards users), patient but joyful. These were functional constraints rather than aesthetic directions. A user logging stool frequency three times a day needs to feel like the app is on their side, not embarrassing them or lecturing them.

I built the brand guidelines directly into the design system rather than documenting them separately. This meant implementing the new visual language first into the onboarding feature — the highest-stakes first impression — and using that as the proving ground before rolling it across the rest of the product.

The design principle: The product should behave, feel, and speak like the brand. A safe space is built through usability and emotional consistency, not just visuals. Product + brand = user satisfaction.

The tracking challenge was a dual brief: the medical team needed structured, high-quality data to run their research protocols. Patients needed a tracking experience that felt guided and manageable, not burdensome. These two goals required the same solution.

The onboarding flow was redesigned to capture each user's specific diagnosis upfront. This wasn't administrative — it was functional. Knowing whether a user had IBS, Crohn's disease, IBD, or another condition meant the tracking experience could be tailored to the specific data points clinically relevant to them.

It also served three simultaneous purposes: it set user expectations for the tracking commitment required, it allowed the research team to prioritise by condition cohort, and it made users feel seen — not routed through a generic experience.

Rather than asking users to track everything every day, the system was designed to guide users toward the data points most relevant to their current phase and condition. It would suggest changes based on observed patterns, nudge at meaningful moments, and feed signals back to the research team about data quality and treatment adherence.

Users track on their own terms, at their own pace — but within a structure that ensures the data is clinically useful.

Working at the intersection of medical research and consumer product required an unusually structured design process. The work wasn't just about shipping features — it was about building a methodology that the whole organisation could trust and operate within.

User interviews. Preparing scripts and testable prototypes before each round. Gathering and prioritising insights against clinical and product goals. Rapid iteration between research and redesign cycles.

Engineer comms. Frequent research finding updates to keep engineering aligned. Adapting to their constraints while holding firm on design requirements. Early-stage experimentation to de-risk implementation.

Research. Documentation and timelines shared across teams. Translating clinical requirements into product specifications. Designing directly with the medical research team.

Acting on data. Module completion rate as primary engagement signal. Volume of tracked data points per user session. Scheduled checkup results as a longitudinal health marker.

Converting & keeping users. Word-of-mouth as the primary growth signal to optimise for. Always verify user sentiment before implementing new features. Delight above logic — emotion drives retention in health apps.

This has been one of the most rewarding products I've worked on. Building something with direct impact to people's health allows you to put maximum effort into your craft — every decision carries real consequences for real patients.

The DiGA approval process forced a level of design rigour that's rare in consumer products. Medical device certification doesn't allow for vague UX decisions — every interaction needed documented rationale, clinical backing, and demonstrable user benefit.

The most important lesson: in health products, emotional safety is a clinical outcome. An app that makes users feel judged or ashamed about their symptoms will be abandoned regardless of its clinical validity. The brand and the product had to work as one.