The main reason software projects run late and over budget is not bad coding, but an unclear agreement on what is being built. A requirements specification describes what the app should do, for whom, and how you will know it is finished. You don’t need technical knowledge — you need clarity. Below is a template you can copy.
In short
Describe the problem and goal, the users and their roles, the main steps users go through, a feature list with priorities (must / should / later), data and integrations, requirements for speed, security and languages, budget and deadline, what is out of scope, and how you will check that the work is done.
A 10-point specification template
- Problem and goal — what doesn’t work today or takes too much time, and what you want to achieve. E.g. “30% of appointments are missed because customers forget” → “reduce no-shows with automatic reminders”.
- Users and roles — who uses the app: customer, staff, administrator. What each role may see and do.
- Main flows — 3–7 steps for the most important actions. E.g. “Customer picks a service → picks staff → picks a slot → confirms → receives an SMS”.
- Feature list with priorities — mark every feature as must, should or later. This affects the price of the first version more than anything.
- Data — what is stored (customers, orders, documents), where existing data comes from, and whether it must be migrated from Excel or an old system.
- Integrations — card payments, invoicing or fiscal systems, accounting, email/SMS, existing systems.
- Platforms and languages — web, iPhone, Android; which languages; whether it must work offline.
- Non-functional requirements — speed, number of users, security and data protection (GDPR), accessibility, backups.
- Budget, deadline and out of scope — an indicative budget, a target date and what is explicitly not part of this phase.
- Acceptance criteria — how you will check a feature is done. E.g. “Cancellation is possible up to 12 h before; after that the button is disabled.”
Example of a well-described feature
| Poor | Good |
|---|---|
| “The app should have reminders.” | “The customer gets a push notification 24 h and 2 h before the appointment. If notifications are off, an SMS is sent. The admin can edit the message text.” |
| “Reports for management.” | “Every Monday at 8 am the manager receives an email with bookings, cancellations and revenue per staff member for the previous week.” |
Common mistakes that raise the price
- “Like app X, just for us” — without a feature list the developer has to guess, so quotes are not comparable.
- Everything is a must — the first version becomes big, expensive and late. Separate what the app cannot work without.
- Forgotten admin side — who enters prices, slots and users? That is often half the work.
- No acceptance criteria — at the end everyone argues about what “done” means.
- Unclear ownership — state in the specification or contract that source code, data and access are yours.
If you are preparing a public tender, also read technical specification for a website tender. For indicative prices see how much a mobile app costs and custom software vs off-the-shelf.
Have an idea but no specification?
Send a few sentences about what you want. I’ll help turn it into a clear specification with priorities — and you’ll get an indicative price for the first version.
Engimotive · Published November 5, 2026