The challenge
A smart-lock maker needed an app that lets owners activate locks, verify their identity and safely share access with family or colleagues — without any user being able to read or change someone else’s data.
What we built
- Lock activation by serial number
- Email OTP verification
- Sharing access between users, with accept and reject flows
- Server-side sharing logic in Cloud Functions using transactions
- Hardened database rules so each user can only access their own records
Why it matters
Moving sensitive operations to the server closed a class of access-control problems that client-only apps often have, while keeping the app fast and simple for users.