How Long Does It Take to Build an App: Real Timelines by Project

After "how much does it cost?", this is the question we hear most. Building an app takes 8 to 12 weeks if it's a tightly scoped MVP, 4 to 6 months if it's a mid-complexity app with its own backend, and 6 to 12 months for complex products like fintech, health, or marketplaces. The real timeline depends less on how fast the team works than on three factors: how clear the scope is, how many external integrations are involved, and the discipline not to add features halfway through. Here are the real timelines stage by stage, what you can compress, and what you can't.

How long it takes to build an app by project type

Project type	Examples	Realistic timeline	Typical team
MVP / validation	Booking app, catalog with ordering, mobile MVP	8-12 weeks	2-3 people
Mid-complexity app	In-house delivery, loyalty app, internal app with offline	4-6 months	3-5 people
Complex app	Fintech, telemedicine, two-sided marketplace	6-12 months	5-8 people
Wrapper / packaged PWA	Turning an existing website into an app	3-6 weeks	1-2 people

These ranges assume a dedicated team and a client who responds. If the project gets done "whenever there's time" between other things, multiply by 1.5 or 2.

The stages, one by one

1. Discovery and design: 2-4 weeks

Requirements gathering, user flows, wireframes, and screen design. It's the stage that's most tempting to cut and the most expensive one to cut: every decision not made here gets made later in code, where fixing it costs 5-10 times more.

2. Development: 6-16 weeks (the big variable)

Backend, app, and the connection between them. Complexity rules here: a list screen with a detail view might take 3 days; a card payment flow with validation and error handling, 3 weeks. If the app is cross-platform with React Native or Flutter — a decision we break down in React Native vs Flutter — the same development covers iOS and Android with 15-20% extra effort, not double.

3. Testing and stabilization: 2-4 weeks

Testing on real devices, bug fixing, performance tuning. It's the stage optimistic timelines skip and the main reason "almost ready" apps take two more months to ship.

4. Store publishing: 1-2 weeks

Google Play usually approves in 1 to 7 days. Apple reviews in 24-72 hours, but the first submission of a new app is frequently rejected over metadata details, permissions, or guidelines — leave margin for a fix-and-resubmit cycle. We cover the full process in how to publish an app on Google Play and the App Store.

Which stages you can compress and which you can't

Compressible:

• Design, if you start from proven patterns instead of inventing every interaction. A good design system saves 1-2 weeks.
• Backend, if you reuse existing APIs or managed services (authentication, notifications, storage) instead of building everything by hand.
• Scope: the most powerful lever. Cutting from the MVP everything that doesn't validate the hypothesis can turn 6 months into 10 weeks.

Not compressible:

• Testing. You can test less, not faster. And testing less gets charged back in production, with real users and public reviews.
• Store review. Apple doesn't serve those in a hurry; there's no reliable way to skip the queue.
• Third-party integrations. If your app depends on a payment gateway's API, an ERP, or a government system, the timeline is set by the slower of the two. An integration with an old management system can take longer than an entire new feature.

Have a deadline and not sure you'll make it? Book a 30-minute call and we'll tell you what scope is realistic for your timeline — and what it would leave out.

The 4 factors that stretch timelines (with numbers)

1. Scope changes. Each medium-sized "while we're at it, let's add..." costs 1-3 weeks across design, development, and re-testing. Three medium changes turn a 4-month project into a 6-month one. It's the most common mistake among those we list in mistakes when hiring app development.
2. Client delays. Access that doesn't arrive, pending content, decisions waiting on a committee. In our experience, between 15% and 30% of a typical project's calendar goes to avoidable waits on the client side.
3. External integrations. Payment gateway: 2-4 weeks. E-invoicing: 2-3 weeks. ERP or legacy system with no documentation: an unknown that can be a month.
4. Regulatory requirements. Fintech or health apps add weeks of security, auditing, and compliance that can't be fully parallelized.

How to read the timeline in a proposal

When a proposal lands, look for these signals:

• Does it have an explicit testing stage? If the timeline jumps from "development" to "launch", you'll be doing the testing yourself, with your users.
• Does it reserve margin for store review? If the delivery date matches the last day of development, nobody counted the approval cycle.
• Does it define what's in and what's out? A timeline with no closed scope is a wish. Ask for the list of included features, in writing.
• Does it have intermediate milestones with deliverables you can see? "50% progress" isn't verifiable; "you can create an account and place an order" is.
• Does it specify what it needs from you and when? If your part isn't in the timeline, delays will be "your fault" without anyone having warned you.

Why to distrust "I'll have it for you in 3 weeks"

There are three ways to deliver an app in 3 weeks, and none of them work in your favor:

1. It's a no-code template with your logo. It can work for validation, but it's not yours, it doesn't scale, and migrating later costs the entire project — we compare them in no-code vs custom development.
2. It has no real backend. An app with no server of its own is a demo. When you ask "and where does my customers' data get stored?", the timeline comes clean.
3. They cut testing and security. The app ships in 3 weeks and breaks in week 4, with real users inside.

An honest 8-10 week MVP always beats a "complete" 3-week app that has to be rebuilt.

When you should NOT rush development

Let's be honest: sometimes the right answer is to wait.

• If you haven't yet validated that anyone wants the product, rushing development only makes you fail faster. Validate with a landing page, a PWA, or interviews before investing months.
• If your deadline is a specific event (a trade show, a launch), consider arriving with a trimmed, honest version rather than a complete, unstable one. The first impression on the stores doesn't get a second take.
• If the budget doesn't match the timeline, compressing with more people has diminishing returns: doubling the team doesn't cut the time in half, and on small projects it can even slow things down.

Timelines with a fixed date and price

At Deepyze we work with a defined scope before we start, verifiable milestones every 2-3 weeks, and timelines that include testing and store review from day one — because a timeline that skips stages isn't optimism, it's debt. If you want to know exactly how long your app would take, tell us about the project: within 24 hours you'll have a proposal with a fixed price, a realistic timeline, and a mobile app development team working in your time zone.