In many small and mid-sized businesses, an Excel or Google Sheets file has become the company’s real software: order tracking, scheduling, quotes, inventory. It was created in an afternoon, it grew over the years, and today everyone depends on it… without anyone really daring to touch it.
Turning it into an app does not mean throwing everything away: your file is the best possible requirements document, since it already contains your data, your columns and your rules.
Signs it is time
- Several versions are circulating (“schedule_v3_final_JM.xlsx”) and nobody knows which one is right.
- Formulas break as soon as a row is inserted in the wrong place.
- Several people need to edit at the same time, and get in each other’s way.
- Data is re-entered in another tool (invoicing, CRM, emails).
- The file is slow or goes beyond the reasonable limits of a spreadsheet.
- There are no permissions: everyone can see and delete everything.
- The file is used in the field, on a phone where it is unreadable.
What an app adds
- A single up-to-date version, shared in real time.
- Forms that prevent input errors (dates, amounts, required fields).
- Role-based permissions: everyone sees and edits what concerns them.
- A history of who changed what and when.
- Automations: alerts, reminders, generated documents (quotes, delivery notes, invoices).
- Comfortable mobile use, even offline if needed.
The 5-step method
- Analyze the file: which tabs, which columns, which formulas, who uses it and for what.
- Separate data from rules: the columns become a database, the formulas become reliable business rules.
- Design the screens: one screen per use (entering an order, viewing the schedule, approving a quote), tested as a mock-up.
- Develop in batches, starting with the most frequent daily use.
- Import the data from the file, check it, then switch the team over.
Options to suit your needs
| Situation | Suitable option |
|---|---|
| A single user, little data | Keep the spreadsheet, better structured |
| A few users, simple needs | A no-code tool such as an online database |
| A team, business rules, documents to generate, mobile use | A custom business app |
A focused business app generally costs $6,800 to $22,500 (€6,000–€20,000)excl. VAT and takes 1 to 3 months to develop. The cost-effectiveness calculation is detailed in the guide on choosing between a business app and SaaS subscriptions.
My advice: send me an anonymised copy of your file before our first call. Ten minutes of reading is often enough to see what should become an app, and what can stay a spreadsheet.