Let Digital Help Everyone Be a Solo Company
Invoicing, job tracking, and a growing family of offline tools — digital independence for one-person businesses. Your data stays on your device.
Digital Independence for One-Person Businesses
You shouldn't need a team of 50 or a cloud subscription to run a digital business. One person, one hand, tools that keep your data on your device — that's all it takes.
Privacy by Default
Your data stays on your device. No cloud sync, no tracking, no analytics SDKs. Every tool we build or champion stores data locally and encrypts backups with AES-256.
Open & Transparent
Open-source where possible. Clear pricing — InvoYX at €9.99/month, TaskSnap at €6.99/month, both after free trials. No dark patterns, no hidden fees, no auto-renewal traps.
Everyone Included
27 languages in InvoYX, 29 in TaskSnap — with independent UI and document language settings. RTL Arabic with Eastern Arabic numerals. Cyrillic, CJK, Latin. Accessibility built in — WCAG 2.1 AA.
Solo-First Design
No enterprise bloat. No team features you'll never use. No "invite your colleagues" prompts. Every feature is built for exactly one person: the solo founder running their business.
Tools Built for One-Person Businesses
Purpose-built apps for solo founders, freelancers, and craftsmen. No cloud. No compromise. No enterprise bloat — every one of them private by design.
InvoYX
Offline Invoicing AppProfessional invoicing for craftsmen and freelancers — 100% offline. Create invoices, quotes, credit notes, and vouchers in 27 languages. Export ZUGFeRD 2.2 / Factur-X hybrid PDFs with embedded XML for DATEV auto-import. AES-256 encrypted backup keeps your data safe on your device — never on a cloud server.
- ZUGFeRD 2.2 / Factur-X PDF with machine-readable XML
- 27 languages — UI and document language independent
- AES-256 encrypted local backup & restore
- DATEV CSV export (42-field Buchungsstapel)
- Voucher system, 3-level dunning (Mahnwesen), expense tracking
- Payment receipts with SEPA QR codes
- PIN app lock (SHA-256), dark mode, RevenueCat subscription
7-day free trial, then €9.99/month. Cancel anytime.
Get InvoYX on Google Play Download on the App Store 🧾 Free Invoice Template — no signup 🇩🇪 Kostenlose RechnungsvorlageTaskSnap
Job Tracking for TradespeopleTrack jobs, hours, photos & materials — 100% offline. Snap before-and-after photos, log materials and costs, and hand every customer a clean, digitally signed PDF report. No account, no cloud, no data collection — your job and customer data never leaves your phone.
- Time tracking — automatic timer or manual entry, to the minute
- Job photos from camera or gallery, attached to each job
- Materials & costs — quantities and prices, auto-summed
- Customer management with full job history
- Digitally signed PDF reports with your logo & company info
- Recurring jobs, dashboard, light & dark mode
- 29 languages — German and English fully covered
14-day free trial, then €6.99/month. Cancel anytime.
Get TaskSnap on Google Play Download on the App Store View TaskSnap → 📘 TaskSnap Guide 🇩🇪 TaskSnap AnleitungBabyTrack
Baby TrackerOffline baby tracker — log feeding, sleep and nappies, with growth curves and reminders. No cloud, no data selling, GDPR-safe by architecture.
- Feeding (breast/bottle/solid), sleep duration, nappy & milk-consumption log
- Growth curves — weight, height & head circumference, offline WHO percentiles
- Milestones & health log (medication, vaccination, temperature)
- Pumping & breast-milk stash tracking (pumped vs consumed)
- Feeding reminders (2/3/4/6h) + daily bedtime reminder
- Paediatrician-ready A4 PDF + memory photo-PDF (8 designs)
- 7-day, 30-day & weekly trend charts + full-text search
14-day free trial, then €4.99/month
View BabyTrack → Get BabyTrack on Google Play Download on the App StoreTellerKalk
Food CostOffline food-cost calculator for food trucks and pop-ups — build recipes with ingredients, and see cost per portion and food-cost % instantly.
- Recipes & ingredients with quantities, prices & units
- Cost per portion, food-cost % & yield/shrink calculation
- Margin → suggested selling price (net/gross with VAT)
- EU-14 allergen tracking & full nutrition (kcal, protein, carbs, fat)
- Menu builder — 3 PDF designs with allergen & kcal legend
- Sales tracking with calendar, photos & receipt PDFs
- Menu engineering (stars / puzzles) + 13 currencies
14-day free trial, then €9.99/month
View TellerKalk → Get TellerKalk on Google Play Download on the App StoreAutoLog
Mileage LogOffline mileage log — record trips with kilometres and purpose, split business & private, and get a GoBD-compliant PDF for the tax office.
- Trip log — odometer km, purpose, date, business/private split
- GPS auto-tracking — live distance, auto-stop after 2 min idle, Haversine
- User-set kilometre allowance (€/km) applied automatically
- Tax-compliant PDF logbook for 39 countries (DE GoBD · AT EStG · CH)
- Multi-vehicle support — name, plate, photo, per-vehicle filter
- Receipt photos embedded in the PDF + reverse-geocoded start/stop
- Digitally-signed PDFs, single-trip route-map PDF, CSV & WhatsApp share
14-day free trial, then €4.99/month
View AutoLog → Get AutoLog on Google Play Download on the App StoreCoachMate
Teaching PlannerOffline studio planner for music teachers, tutors and coaches — manage students, plan lessons, and send SEPA invoices, all on-device.
- Students with contacts, notes & hourly rate + contact import
- Lessons with date, duration & auto-computed fee + month calendar
- Lesson packages with remaining-hours, refund & per-package goals
- SEPA-QR invoices (EPC-compliant) with VAT for 39 countries
- Progress & goals per student (1–5 rating chart)
- Invoice status (open/paid) & auto-numbering, digitally-signed PDFs
- Lesson reminders (30 min–1 day), CSV export & WhatsApp share
14-day free trial, then €7.99/month
View CoachMate → Get CoachMate on Google Play Download on the App StoreSammelCheck
Collection CatalogOffline catalog for your collection — coins, stamps, sneakers, watches. Track value, condition and location, with a total-value dashboard and PDF export.
- Items with value, condition, quantity, purchase & sell price, location
- Size / grade field (shoe size, PSA grade) + category manager
- Item history (buy / sell / move) & per-item value-history chart
- Customers & sales with invoice PDF + contact import
- Barcode / QR scan (EAN, UPC, Code128, QR, DataMatrix)
- Multiple photos per item + PDF catalog, CSV & WhatsApp share
- Dashboard, search & filters (collection / wishlist / sold)
14-day free trial, then €5.99/month
View SammelCheck → Get SammelCheck on Google Play Download on the App StoreBuilt by a Solo Founder, for Solo Founders
The One Hand was started in Vienna, Austria by Bilal Shadid — a developer and digital skills trainer who watched too many solo business owners upload their entire financial lives to cloud platforms they didn't control.
The name comes from a simple observation: a solo founder runs their entire business with one hand. They write invoices, track jobs, manage clients, log hours, and file taxes — all alone. The tools they use should respect that reality, not punish them with enterprise complexity or cloud surveillance.
Every product we build follows three rules: your data stays on your device, pricing is transparent and fair, and the tool works offline — no internet connection required after install.
We're based in Vienna. We ship globally. We don't track you.
Manuals & Guides
Every feature of every app, explained step by step with screenshots — in English and German.
TaskSnap Guide
Profile & document language, PDF report settings, company data, encrypted backups, customers, jobs with timer, checklist, photos, materials, signature — and the dashboard.
TaskSnap Anleitung
Profil & Dokumentsprache, PDF-Bericht, Firmendaten, verschlüsseltes Backup, Kunden, Aufträge mit Timer, Checkliste, Fotos, Material, Unterschrift — und das Dashboard.
InvoYX Guide
Company data, bank details & payment QR code, tax numbers, invoices, quotes, credit notes & refunds, dunning, accounting exports and backups.
InvoYX Anleitung
Firmendaten, Bankdaten & Zahlungs-QR-Code, Steuernummern, Rechnungen, Angebote, Gutschriften & Rückzahlungen, Mahnwesen, Exporte und Backups.
BabyTrack Guide
Feed, sleep & nappy tracking, feeding and bedtime reminders, growth curves with WHO percentiles, health log and memory PDF export.
BabyTrack Anleitung
Füttern, Schlafen & Windeln erfassen, Fütter- & Schlafenszeit-Erinnerungen, Wachstumskurven mit WHO-Perzentilen, Gesundheits-Log und Foto-PDF-Export.
CoachMate Guide
Students & contact import, lesson planning with reminders, packages, progress tracking and SEPA-QR invoices.
CoachMate Anleitung
Schüler & Kontakt-Import, Lektionsplanung mit Erinnerungen, Pakete, Fortschritts-Tracking und SEPA-QR-Rechnungen.
SammelCheck Guide
Item catalog with value, condition and photos, value history, customers & sales and PDF export.
SammelCheck Anleitung
Objekt-Katalog mit Wert, Zustand und Fotos, Wertverlauf, Kunden & Verkäufe und PDF-Export.
AutoLog Guide
Trip logging, business/private split, GPS tracking, kilometre allowance and the GoBD-compliant mileage-log PDF.
AutoLog Anleitung
Fahrten erfassen, Geschäftlich/Privat-Trennung, GPS-Tracking, Kilometer-Pauschale und GoBD-konformes Fahrtenbuch-PDF.
TellerKalk Guide
Recipes and ingredients, yield and shrinkage, margin-based selling price, VAT and food-cost PDF.
TellerKalk Anleitung
Rezepte und Zutaten, Yield und Schwund, margenbasierter Verkaufspreis, USt und Food-Cost-PDF.
Thoughts on Solo Digital Life
Practical guides for running a one-person business. No fluff — just real experience from solo founders, for solo founders.
How to Write an Offer (Angebot) That Actually Wins the Job
An offer is a sales pitch, not a price list. The four-block structure that gets the job — and the legal fields every offer must include.
Time Tracking for Tradespeople: Why Remembering Is Costing You Money
You bill from memory, and memory rounds down. What undocumented hours really cost you, and the 30-second fix.
Food Cost Percentage: The One Number That Decides If Your Dish Makes Money
If you don't know your food cost %, you're pricing blind. The formula, a worked example, and where kitchens leak profit.
Fahrtenbuch Rules in Germany and Austria: What the Tax Office Actually Requires
A Fahrtenbuch only counts if it's complete, accurate and in the right form. Here's what the tax office checks.
How to Organize One-on-One Lessons Without Double-Booking
Music teacher, tutor, or coach — the problems are the same: scheduling, no-shows, and tracking who's paid.
How to Catalog Your Collection Properly (Coins, Cards, Sneakers & More)
A collection without a catalog is just a pile of stuff. What to record — and why it matters for value, insurance and selling.
Baby Feeding and Sleep Tracking: A Simple Guide for New Parents
Tracking feeding and sleep helps you and your pediatrician. What's actually worth logging, and what you can skip.
How to Write an Invoice as a Tradesperson
The 8 things every legal invoice needs, the mistakes that delay payment, and a free template to start today.
Track Jobs and Hours as a Solo Tradesperson
How to log time, photos and materials on every job — and prove it to the customer with a signed report.
Mileage Log for Tax: What the Tax Office Actually Needs
The entries a valid Fahrtenbuch requires, the country-by-country rules, and why a digital log beats paper.
ZUGFeRD & Factur-X Explained — One PDF, Two Formats
How a single hybrid PDF can replace manual data entry, satisfy your accountant, and save you hours every month.
How to Get Paid Faster as a Contractor
Seven rules that end the 60-day wait — same-day invoicing, deposits, and payment terms that actually work.
Why Offline Invoicing Matters — Privacy, Speed, and Digital Sovereignty
Most invoicing apps send your client data to the cloud. Your full client list, revenue history, and financial fingerprint — on servers you don't control. Here's why offline-first is the answer.
The Solo Founder's Toolkit: 7 Privacy-Respecting Apps
A curated, opinionated list of tools that help you run a business without becoming the product.
Ready to Run Your Solo Business?
Invoice with InvoYX, track jobs with TaskSnap — both keep your data on your device, offline and private.