Fieldline

A concept mobile app for field service technicians. Today's jobs, the route between them, and notes that save with no signal.

ConceptFictional project. No real client, and nothing here is a measured result.

Sector: Field services
Service: App development
Year: 2026

Concept design: Fieldline

10:21

WO-2291

Notes

0:24

Door seal worn on the hinge side.

On phone

Asked about a quote for a new door closer.

On phone

10:28

Today

3 of 6 stops

Next stop

Walk-in chiller fault

Cold store, Unit 4, Quarry Road

Arrive10:40

Drive6.3 km

Booked90 min

Start job

4Oven extraction12:15

10:52

WO-229100:12

Walk-in chiller fault

Cold store, Unit 4, Quarry Road

Isolate power

Check door seals

Compressor amps8.4 A

Test defrost cycle

Customer sign-off

RouteJobNotesParts

Back in signal3 notes synced

// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}

// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}// Notes save to the device first. Signal is optional.export async function saveNote(job: Job, draft: NoteDraft) {  const note = { ...draft, jobId: job.id, status: 'queued', at: Date.now() };   await db.notes.put(note);  await outbox.push({ type: 'note.create', payload: note });   if (await network.isOnline()) {    await outbox.flush();  }   return note;}

In this concept

iOS and Android
Offline first
Route planning
Job sheets

Fieldline is a concept project. There is no real client behind it. We made it to show how we would approach an app for people who work away from a desk. Everything below describes design goals, not measured results.

The problem

A service technician’s day runs on a van, a phone, and whatever signal the building allows. Jobs arrive by call or text. Addresses sit in one app, job history in another, and the notes end up on paper, typed in again at home.

The worst moments come in plant rooms and basements, where most apps stop working. A form that cannot save is a form nobody trusts, so the paper stays in the van.

The approach

We would start in the van, not in a meeting room. Ride along for a few days, watch where the phone comes out, and note what gets written down instead of typed.

Three decisions would shape the rest of the work:

The device is the source of truth. Every screen reads from local storage and every action saves there first. Sync runs in the background and never blocks the job.
One hand, bright light, gloves on. Large targets, strong contrast, a daylight mode, and the next action always in the same place.
The day is the home screen. Open the app and see the next stop, how long it takes to reach, and what the job needs.

What we would build

A cross-platform mobile app for iOS and Android, with a local database and an outbox that retries when signal returns.
A route view that orders the day’s stops and reorders them when a job runs over.
Job sheets with checklists, readings, parts used, photos, and customer sign-off.
Offline notes by voice, photo, or text, attached to the job and marked clearly as saved or synced.
A small dispatch console so the office can assign jobs and see what has come back.

Goals, not results

The goals we would design against: a technician closes a job without typing anything twice, loses nothing when signal drops, and never has to ask whether a note was saved.

Key screens

Route

The day on one map. Finished stops fade, the next stop sits in a sheet with its arrival time, and one button starts the job.

Job sheet

Everything for one visit in the order it happens, from the checklist through to sign-off. Daylight mode keeps it readable outdoors.

Notes

Hold to record, tap to add a photo, or type. Each note shows where it lives right now, on the phone or synced, so nobody has to guess.