An invoice app where a duplicate number is impossible
Estimates and invoices from a phone to a PDF in the share sheet — offline, no account.
- Fakturo
- Fintech, year 2026
- Status
- Feature-complete iOS build; launch checklist in progress
- PDF templates
- 4
- PDF templates
- unit tests on money and numbering
- 46
- unit tests on money and numbering
Problem
Freelancers and micro-businesses in the US and Latin America needed invoices without a subscription SaaS: fast, offline, correct numbers, a PDF they can send in seconds.
What we did
- Kept all data on the device in SQLite — no server, no account, instant start.
- Allocated document numbers inside a transaction with a unique index, so duplicates cannot exist at the database level.
- Stored money in integer minor units and tax in basis points, with the arithmetic covered by tests.
Result
A complete iOS product with four PDF templates, three languages, reversible backups and a monetisation policy that can be switched without a release.
Modules
- Documents and numberingEstimate to invoice conversion with an audit link; transactional number allocation.
- PDFFour templates, HTML-escaped client data, Letter or A4 chosen from locale, iOS share sheet.
- Money and statusMinor units, basis-point tax, half-up rounding; overdue is derived, never stored.
- BackupJSON export/import validated by a strict schema, with an automatic pre-import backup.
- MonetisationFree-limit or watermark policy as a switchable union; RevenueCat entitlement, no-op when unconfigured.
Technology
Expo, React Native, SQLite, Zod, RevenueCat
All workFree call: 30 minutes and a written summary
We talk about your business. No obligation on your side.