Patudo
Mobile App Design
Problem: when two people share a pet's care, doses get doubled or skipped, and records live in a paper booklet.
What I did: desk research, a state matrix of six dose moments, nine mobile screens and three flows, and a heuristic review of my own screens.
Outcome: every dose logged with the real date and who gave it. 9 issues found, 2 major, all fixed. Not yet tested with pet owners.
Patudo (Portuguese slang for a fluffy, big-pawed dog) is a concept app that helps pet owners in Portugal keep up with their pet's health routine: vaccines, deworming, medication, weight and vet visits, shared with everyone who looks after the animal.
Role:
Product Designer
Year:
2026
Explore the full story –
Challenge
In Portugal, dogs must be microchipped by 120 days old and keep a valid rabies vaccine, with fines from €50 to €3,740 (DGAV). Preventive care is easier to forget: in a manufacturer-funded European survey, around half of owners admitted missing an antiparasitic dose in the past year. Records live in a paper booklet, and when two people share the care, doses get doubled or skipped.
Objective
A calm, reliable routine: a care plan that starts from Portuguese legal requirements, a Today view by pet and carer, one-tap logging with the real date and who gave the dose, and a health record to share with the vet. The app records and reminds; it never diagnoses.
Results
The state matrix set the screen, tone and single action for each moment, from on time to late, before any screen was drawn. A heuristic review of my own screens found 9 issues, 2 of them major, all fixed. Not yet tested with pet owners.
Key insight
Pet care rarely fails because people don't care. It fails when two people share one routine and nobody can see who gave the last dose, or when.
Process
Discover. DGAV legal requirements, ESCCAP guidance, published studies and five competing apps with their App Store reviews.
Principles. Record the real date and who gave the dose. Start from Portuguese law, then add the vet's advice. Calm tone. Never diagnose.
State matrix. Six moments of a dose (on time, due today, late, two carers, medication course, vet visit), each with what the screen shows, the tone and one action.
Review and fix. A heuristic review found 9 issues. The 2 major ones: a booked visit still offered “Book”, and the late-dose screen guessed the real date for the user.
Success metrics
These are the targets I would use to judge a pilot. They are goals, not measured results: the product has not been built or tested.
At least 90% of doses logged within two days of the due date.
No doubled doses in households with two or more carers.
The health record exported before at least half of vet visits.
A new pet set up in under three minutes.
Shipped & next
Left out on purpose: symptom checking or any medical interpretation, shopping and clinic integrations.
Next: a test with 5–6 households where two or more people share the care. Tasks: log a dose a partner may already have given, handle a dose two days late, invite a pet sitter, export the record for the vet. Success: real dates logged and no doubled doses.