FaultExpert Mobile Office

Invoices and job paperwork — built in the truck, for the truck.

Local-first invoicing for industrial & mobile repair techs. Your data lives on your phone — works offline, exportable forever, no monthly ransom to keep your own invoices.

Get the Founding Tech License — $49 one-time First 25 techs · then $79 · 14-day refund Try the live demo — no signup Or test it free — founding tester slots

$49. Once. Not $49 a month. You buy it, you own it — unlimited invoices, every feature included.

Built different — on purpose

The app is a one-time purchase. Nothing to cancel, nothing expires. No auto-renew, no card on file, no surprise charge eleven months from now. Optional add-ons (AI diagnosis, hosted sync, annual code refresh) are subscriptions you can cancel anytime — the app keeps working, full speed, forever, when you do.
Nobody can hold your money. Customers pay straight to your Venmo, Zelle, or Cash App — no processor in the middle taking a cut or freezing your account.
No account. No login. No lockout. Nothing to get locked out of, and no server to go down on the day you need to bill.
Your business is a file you own. One-tap backup to your own Dropbox or Google Drive, CSV and QuickBooks export anytime. Even if this company vanished tomorrow, your invoicing keeps working.
Works forty miles past the last cell tower. The whole office runs on your phone — basements, mechanical rooms, rural plants. Sync when you're back in signal.
Every keystroke survives. Switch apps mid-invoice, take the call, come back — your draft is still there.
No telemetry. No silent uploads. The database is a file you own — we can't leak what we never collect. Read the Trust Pledge.
313 field-curated fault codes — built and verified by a working industrial tech on real jobs, not scraped from manuals. Built to grow: confirmed fixes are de-duplicated, quality-checked, independently verified, and human-reviewed before they ship to everyone.

Everything the paperwork side of the job needs

Today dashboard — what you're owed, what's overdue, one tap to chase
Get-paid handles — Venmo / Cash App / Zelle on every invoice you send
Invoices, quotes & sales orders
Payments & balances
Customers, items & price levels
PDF invoices — print, email, text
Signatures & job photos
Works fully offline
Sync via your own Dropbox / Google Drive
Bring your existing books — one-tap .db import or CSV mapping
CSV import/export · QuickBooks export
Runs on Android, iPhone & desktop (PWA)
Built by a working field tech — not a software company.
I program PLCs and fix industrial equipment every week, and I invoice every job from my truck with this exact app. No vendor cloud holding your books hostage, no $30/month forever. Your invoices live in a single database file you own — back it up, export it, take it anywhere.
$49 one-time$79
Founding Tech License — first 25 buyers only. Lifetime use · free updates to the core app · email support included for 12 months (24–48h, business days), best-effort after · 14-day money-back guarantee.
Buy now — instant access

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