Turning idle cars into shared mobility — a digital key concept for an automotive innovation lab.
Context
A confidential design sprint for the digital and mobility innovation arm of a global car manufacturer, framed as part of a recruitment process — two weeks, solo, hi-fi prototype as the deliverable.
The starting observation was simple but striking: a private car spends roughly 95% of its life parked. That single number reframes the whole industry — every minute of idle time is unrealized utility, and every owner is potentially also a host.
The brief: design a mobile app concept that lets an owner share their vehicle with someone they trust — a friend, a partner, a family member — through a secure digital key, instantly and without paperwork.
01
Frame the product around the moment, not the marketplace
Most car-sharing apps lead with a marketplace — search, browse, book. That framing makes the owner a passive supplier. I flipped it: the experience starts from the owner's intent — "I'm not using my car this weekend, share it with Marc" — and builds outward from that single outbound action.
02
A digital key that feels physical
A digital key is abstract by default — it lives in a database, behind an auth flow. The prototype tied it to tangible interactions: a swipe to grant access, a clear validity window with countdown, a physical-feeling lock/unlock screen on arrival. Trust comes from feedback, not from screens that say "Secure".
03
Permissions you actually understand
Sharing a car raises real questions: can they drive at night? cross borders? refuel on the owner's account? The prototype broke these out as toggles in plain language, with a single-screen recap before sending the key. No legal-speak, no nested settings — banking-grade permission UX, applied to a vehicle.
2 weeks. Measurable shift.
2 weeks
Hi-fi mobile prototype
Owner-first, not marketplace
What I'd do differently
The brief was framed as a product question, but the real exercise was strategic: how does a manufacturer move from selling cars to selling mobility, without losing the trust attached to the brand? Four years on, the question is more relevant than ever — and the digital key is no longer hypothetical, it's table stakes.
Up next.
Foodhack
Foodhack ran a FoodTech media brand and an engaged investor community. I designed the investment platform that turned their manual, intro-by-intro dealmaking into a product that scaled, shipped fast, and closed real deals.