Ask “how long does it take to build an app?” and the honest answer is that it depends far less on the code than on the scope, the number of platforms and how quickly decisions are made: a focused first version is typically a matter of a few months, while a product with accounts, payments and integrations takes noticeably longer. The surest way to a realistic app development timeline is to size each phase separately, because each one is decided by different things. This article walks through the phases, a table by type of app, store review, what slows projects down and how to shorten the schedule without cutting corners.
Last updated: 30 October 2026.
How long does it take to build an app, and why?
Five things set the length of almost every app project. The first is scope: how many screens, user roles and rules the first release must carry. The second is platforms: iOS, Android, the web, or several at once. The third is integrations: payments, maps, an existing customer database or booking system. The fourth is content and design maturity: whether a brand and copy already exist. The fifth, and the one buyers underestimate most, is the speed of decisions on the client side.
At Odduel, a creative and technology agency in Barcelona and São Paulo, we plan application development phase by phase for exactly this reason: a single number for “the app” hides where the time really goes. If you are still at the stage of deciding what to build, our app development guide sets out the whole process from idea to launch.
In short: an app is not one block of work but a sequence of phases. Discovery and design take a meaningful share of the schedule, the build takes the largest share, and testing and store review are shorter but cannot be skipped. The length of each phase depends on its own drivers. Fix those drivers early and the timeline becomes predictable.
What are the phases of an app development timeline?
Most app projects move through the same six phases. They overlap in practice, especially in agile work, but each has a distinct purpose and a distinct set of things that make it longer or shorter.
- Discovery and scope.
- UX and interface design.
- Technical architecture and set-up.
- Build, in short cycles.
- Testing and quality assurance.
- Store submission, launch and the first fixes.
Discovery and scope
Discovery turns an idea into a written scope: who the users are, what they must be able to do in the first release, what can wait, and which systems the app must talk to. It usually takes a small share of the total schedule, yet it has the largest effect on everything after it.
What lengthens it: several stakeholders with different views, an unclear business model, or regulated data such as health or financial records. What shortens it: one person who can decide, a clear list of what the first release must not include, and existing research on the users.
UX and interface design
Design covers the flows (how a user gets from opening the app to finishing a task), wireframes, and then the finished interface. A clickable prototype at this stage lets real users try the journey before any code is written, which is the cheapest moment to find a problem.
Its length follows the number of distinct screens and states (empty, loading, error, offline), and whether a brand already exists. An app built on an established identity moves faster than one where the logo, colours and type are still being decided alongside the screens.
Technical architecture and set-up
Before the build proper, developers choose the stack, set up the back end, the database, authentication, environments for testing and release, and the accounts on the app stores. The choice between native and cross-platform code is made here, and it changes the build more than any other technical decision; it is worth settling with the trade-offs in cost, speed and device features written down.
This phase is short when the app uses common building blocks and longer when it must connect to older systems with poor documentation.
Build
The build is where the largest share of the time goes. Done well, it runs in short cycles of one or two weeks, each ending with a working version you can install and try. The length depends on the number of features, the complexity of the rules behind them, and the integrations.
AI now carries much of the repetitive production in a good studio: component code, first drafts of tests, data scaffolding. That shortens the build noticeably. It does not shorten the decisions about what the product should do, or the review of what was produced, which stay human work.
Testing and quality assurance
Testing runs throughout the build, but there is always a final period of checking on real devices: different screen sizes, older operating system versions, slow connections, accessibility settings such as larger text and screen readers. Apps that handle payments or personal data need extra security checks.
What lengthens it: many device types to support, offline behaviour, and late changes to scope that reopen screens already tested.
Store submission and launch
An app for iPhone or Android must pass the store’s review before the public can download it. Preparing the listing (screenshots, descriptions, privacy details, age rating) takes real time and is often left too late. After launch there is always a short period of fixes as real users arrive.
How long does it take by type of app?
The table below shows how the main types of app compare. It gives relative length rather than week counts, because the same type of app can vary a great deal with scope; treat it as typical patterns from our experience, not as a promise.
| Type of app | Typical relative length | What lengthens it | What shortens it |
|---|---|---|---|
| Clickable prototype | Shortest: a few weeks is typical | Many user roles to show | A clear single journey |
| MVP with one core journey | Short: commonly a few months | Accounts, payments, admin tools | Strict “not in version one” list |
| Content or brand app | Short to medium | Custom animation, many languages | Existing brand and content |
| Booking or ordering app | Medium | Links to tills, calendars, stock | Standard payment and booking services |
| Marketplace (two sides) | Long | Two sets of users, trust and payouts | Launching one side first |
| SaaS or business web app | Medium to long | Permissions, reporting, integrations | Off-the-shelf sign-in and billing |
| App tied to hardware or regulated data | Longest | Certification, security reviews | Early involvement of compliance |
Two points stand out. Building for iOS and Android at once with one cross-platform codebase usually adds less time than building two native apps, but it is never free: each platform still needs its own testing and store work. And the jump from an MVP to a marketplace is not a matter of more screens; it doubles the number of users whose journeys must work. Our MVP development guide explains how to cut a first version down to what proves the idea.
How long does app store review take?
Store review is the one phase you do not control. Apple reviews every app and every update submitted to the App Store against its published guidelines, and it describes the process and current expectations on its App Review page. Google Play also reviews apps before publication, and its guidance on preparing your app for review explains that review times vary and can be longer for some new developer accounts and app types.
Neither store guarantees a fixed time, so plan for uncertainty rather than a date. In practice:
- Submit a first build well before any public launch date, so a rejection does not move your launch.
- Prepare privacy information, screenshots and test accounts for the reviewer in advance; incomplete listings are a common cause of rejection.
- Read the guidelines for sign-in, payments and user-generated content early in design, not at submission.
- Expect each update to go through review too, which matters when you plan fixes after launch.
What slows app projects down?
When an app is late, the cause is rarely the speed of the developers. It is usually one of the following.
Decisions that wait
Every cycle of the build produces questions: what happens when a payment fails, which fields are compulsory, what the empty screen says. When those answers take a week instead of a day, the schedule stretches by the same amount. A client-side product owner with the authority to decide is the single biggest lever on the timeline.
Content that arrives late
Copy, product data, photographs, legal texts and translations are often treated as something to add at the end. Real content changes layouts, so it reopens screens already designed and tested. Agree early who writes what, and by when.
Integrations that are harder than expected
Connecting to a payment provider, a booking system or an older internal database depends on the quality of that system’s documentation and on the people who look after it. Ask for access and test credentials in discovery, not in the build; an integration that cannot be tested blocks everything behind it.
Scope that keeps growing
New ideas during the build are normal. Adding them to the first release without removing something else is what makes projects slip. Keep a list for version two and protect the first release.
How can you shorten an app timeline safely?
Shortening an app timeline safely means removing waiting and rework, not removing testing or design. These steps work in that order.
- Write a one-page scope with a list of what the first release will not do.
- Name one decision-maker on your side and agree a response time for questions.
- Start with a clickable prototype and test it with a handful of real users before the build.
- Choose standard services for sign-in, payments and notifications instead of building them.
- Prepare content, legal texts and store listing material in parallel with the build.
- Submit to the stores early with an internal test build, so review surprises appear before launch day.
- Release a focused first version and plan the next cycles from what users actually do.
What not to cut: device testing, accessibility checks and security review. Skipping them rarely saves time overall; it moves the work to after launch, when fixing it is slower and more visible. The timeline and the budget move together, so if you are also sizing the investment, our article on app development cost explains how each phase shows up in a quote.
Questions people ask
How long does it take to build a simple app?
A simple app with one main journey, a few screens and no complex integrations is usually the shortest kind of project, commonly a matter of weeks to a few months from scope to store. The exact time depends on how quickly content and decisions arrive and whether the brand and design already exist.
Is it faster to build for iOS and Android at the same time?
Building both platforms from one cross-platform codebase is usually faster than building two native apps one after the other. It is not twice as fast, though: each platform still needs device testing, its own store listing and its own review. Native code can be worth the extra time when the app depends heavily on device features.
Can AI make app development faster?
Yes, for the repetitive production: component code, test drafts, data set-up and first versions of routine screens. A studio that uses it well delivers in noticeably less time. AI does not speed up decisions about what the product should do, user testing or final review, which remain the parts that shape the schedule most.
How long does App Store and Google Play review take?
Neither Apple nor Google promises a fixed review time, and both describe their processes in their official developer documentation. Times vary with the app, the account and the time of year. Plan for uncertainty by submitting an early test build, preparing listings and reviewer access in advance, and never fixing a public launch date to the first submission.
Why do app projects run late?
Most delays come from the client side of the process rather than the code: decisions that wait, content that arrives late, integrations that cannot be tested and scope that grows without anything being removed. A clear first-release scope, one decision-maker and early access to external systems prevent most of them.
When will I get a realistic timeline for my app?
A realistic timeline follows a short brief and a discovery conversation, once the scope, platforms and integrations are known. Before that, any figure is a guess. A good studio gives you a phase-by-phase plan with the assumptions written down, so you can see which decisions on your side move the dates.
If you have an app idea and want to know how long it will really take, send us a short brief: we will come back with a phase-by-phase plan and the assumptions behind it. You can get in touch here, or read how we approach application development.
