Offline-first
Apps that keep working when the connection doesn't
An offline-first app saves every action on the device first and syncs with the server when a connection is available. Staff can keep taking orders, scanning stock or logging readings through a network outage, and nothing gets lost or duplicated when the connection comes back.
Who needs offline-first?
Restaurants and cafés
A POS or ordering tablet that keeps taking orders when the Wi-Fi drops during a rush.
Retail and warehouses
Stock counts and scans in areas with poor coverage.
Industrial and field work
Inspection forms and equipment readings where internet is unreliable or blocked by design.
Mobile workforces
Technicians and drivers moving in and out of coverage all day.
How we build it
Local storage
IndexedDB and the Origin Private File System hold data on the device. We request persistent storage so the browser doesn't clear it under storage pressure.
Service worker
The app shell and assets load from a local cache, so the app opens with no connection.
Outbox queue
Every change is written locally with an idempotency key, then sent to the server. Retries can't create duplicate orders.
Background sync
Where the browser supports the Background Sync API we use it, and elsewhere we retry on reconnect and on app focus.
Conflict resolution
We pick the strategy per data type. Last-write-wins works for simple settings. Field-level merge works for records. CRDTs (Yjs, Automerge) work when several people edit the same document.
Clear UI states
Users can see what's saved locally, what's syncing and what failed. Nothing silently disappears.
Fallbacks for every failure point
We plan for the connection dropping in the middle of a request, a server that's reachable but slow, an expired session after hours offline, and storage running low. Error logs and usage events are recorded on the device while offline and sent once the connection returns, so your team can still see what happened during the outage.
FAQ
Frequently asked questions
01Can a web app really work offline, or do we need a native app?
A well-built PWA works offline on modern browsers. If you need hardware the browser can't reach, we wrap the same code with Capacitor or Tauri.
02Is local data secure?
Sensitive data stored on the device can be encrypted with the Web Crypto API and cleared on logout or after a set period.
Next step
Start with a review of what you have
Send us your repository or a staging link. We'll come back with the three changes that would make the biggest difference to your release speed, performance and reliability.