01 — Context
Inspectors and regulated businesses work through official environmental compliance checklists, often at sites with poor or no connectivity. An earlier native mobile app was being replaced by a lighter installable web app.
02 — Challenge
The app had to work fully offline, keep each user's answers safe on the device (often the only copy), and roll out updates without ever losing data or reloading under the user. It also had to show a reliable compliance picture computed from hundreds of questions.
03 — Approach
Offline-first by construction
An installable progressive web app with an offline-first shell. The whole checklist catalogue ships inside the app, so nothing is fetched at runtime.
Data that survives every update
On-device storage with strict, forward-only schema versioning. Upgrades never drop data, and file export and import let users move to a new phone or recover after clearing the browser.
A compliance picture people can rely on
A dashboard computes law-following and risk-likelihood percentages per sector from the stored answers, never from stored totals.
Specified, then proven
About 100 written requirements across 13 capabilities, a layered front-end architecture enforced by lint, and automated end-to-end tests for offline mode, install, updates, backup and accessibility. The build fails if the host’s caching rules go missing.
04 — Outcome
The field app now runs on any phone browser and installs without an app store. It covers the full official catalogue offline.
- Official checklists
- 11
- Questions, all offline
- 428
- Specified capabilities
- 13
- Written requirements
- ~100