How does app development work? Phases, timeline, team

01Phase 1: requirements and concept (1–3 weeks)

It starts not with code but with a sharp cut: what must the app be able to do in the end, for whom, with which systems behind it?

• Define goals and user groups: who uses the app, in what situation, how often? Platform choice (iOS, Android, web) and feature scope follow from that.
• Clarify systems and interfaces: which existing systems (ERP, CRM, specialist applications) need connecting, who provides access and test data?
• Cut the scope: what goes into the first version, what deliberately does not? A tight first scope is the biggest cost and time lever of the whole project.
• At appDev this step is called Discovery: €1,900, credited when you place the order — it ends with a fixed-price quote.

02Phase 2: design and prototype (2–4 weeks)

Requirements become screens: wireframes for structure first, then clickable prototypes, then the final UI in your brand's look. The prototype is the cheapest moment for corrections — every change made here costs a fraction of what it would cost in development. Testing happens with users from the target group, not in the meeting room.

03Phase 3: development (the longest part)

Frontend (the app itself) and backend (server, data storage, interfaces) are built in parallel, in stages of one to two weeks. Good providers show a runnable interim version after every stage — you see progress in working features rather than status reports, and can steer before anything drifts off course.

04Phase 4: testing and quality assurance (parallel + 1–3 weeks at the end)

Testing runs throughout, not just at the end: automated tests for the logic, device tests on real phones rather than only in the simulator, load and security tests for the backend. The final stretch adds acceptance by your users on real workflows — they notice fastest whether the app holds up in daily use.

05Phase 5: launch and operation

Store approval (the Apple review usually takes one to three days) is its own work package: store listings, screenshots, privacy declarations, test access for the reviewers. Then day-to-day operation begins: monitoring, bug fixing, the yearly OS updates from Apple and Google, new features. Before the project starts, settle who handles that and what it costs.

06How long does what take?

The total duration depends almost entirely on the scope of the first version — the price ranges behave much the same:

• Simple app (one purpose, one platform, few integrations): around 8–12 weeks to a productive version.
• Mid-complexity app (backend, offline mode or both platforms): around 3–5 months.
• Complex app (accounts, deep system integration, high security requirements): from 6 months, often in stages.
• What actually delays projects: late data access, unclear responsibilities on the client side, scope growing during development (“while we're at it…”). All three are avoidable — through phase 1.

07The eight-week question: what is realistic that fast?

Providers promising “your app in eight weeks” always mean a particular scope — and that scope is achievable: one platform, one core feature, a standard backend, data access from week 1. What does not fit in eight weeks: two native platforms, deep ERP integration, offline sync or extensive security audits. The timeline becomes reliable when it rests on a requirements phase — at appDev that is the Discovery for €1,900, ending in a fixed-price quote with a committed date, credited when you order.

08How you can tell the project is on track

You don't have to wait for the final acceptance to know whether the project is on course. Four early signals:

• Runnable interim versions every one to two weeks — as an installable test build on your device (e.g. via TestFlight), not a slide deck.
• A visible stage plan: which features are done, in progress, open — something you can look up rather than have to ask for.
• Demos with real data: the provider shows the current state with your sample data, not with placeholders.
• Early bad news: a provider who raises delays and trade-offs on their own initiative works predictably. One where everything is “on track” until week 10 usually doesn't.

09Who belongs on the team?

A business app typically involves two to five people: project lead, UI/UX design, one to three developers for app and backend, quality assurance. On your side it takes one thing above all: a fixed contact person with decision-making authority who bundles questions, reviews interim versions and organises test users. Projects without this role get slow — regardless of the provider. For the full picture of an app project, see the guide.