How Long Does It Take to Build a Website, Web App or Mobile App?
There is no fixed number, because the timeline is set by three things: how much is being built, how quickly decisions and content arrive, and how many outside parties the project depends on. A website with finished content and few integrations is the shortest kind of project. A web application with user roles, payments and integrations takes longer, and a mobile app adds device testing and store review on top. Any figure quoted before the scope is written down is a guess.
Entrant Technologies builds websites, web applications, mobile apps and custom software. This guide explains what moves the schedule on any software development project, so you can judge an estimate when you receive one.
What phases does every website or app project go through?
Every project goes through the same six phases, whatever its size, and each one has a typical cause of delay. The phases overlap in practice, but none can be skipped.
- Discovery and scope. Agreeing what will be built and for whom. Stretched by unclear goals and by stakeholders who have not yet agreed with each other.
- Design. Screens, user flows and visual style. Stretched by slow feedback, extra revision rounds, and content that is not ready, because layouts built around placeholder text are redone when the real text arrives.
- Development. Building the front end, back end and database. Stretched by requirements that change mid-build and by third-party integrations such as payment gateways, CRMs or shipping carriers, where your team waits on someone else's account approval, sandbox access or documentation.
- Data migration and content loading. Moving records from the old system. Stretched by duplicates, missing fields and inconsistent formats that only appear once the real data is examined.
- Testing. Checking features, browsers, devices, security and performance, then your own acceptance testing. Stretched by late bug discoveries and by acceptance testing that starts late.
- Launch. Hosting, domain changes, final approvals and, for mobile apps, store review.
How long does app store review add to a mobile app timeline?
Store review adds waiting time that neither you nor your developer controls, so it must be in the plan. As of October 6, 2026, Apple's App Review page says App Review typically reviews at least 50% of submissions in less than 24 hours and 90% in less than 48 hours, and that incomplete submissions may be delayed or may not pass. Google's Play Console Help says certain apps and developer accounts are subject to extended reviews of up to 7 days, or longer in exceptional cases.
A rejection means fixing the issue and submitting again, which repeats the wait. Google also requires personal developer accounts created after November 13, 2023 to run a closed test with at least 12 testers opted in continuously for 14 days before applying for production access. Whether you build one codebase or two also affects the schedule; see our comparison of native, Flutter and React Native.
Why does adding more developers not speed up a late project?
Adding people late usually slows a project down, because new developers must learn the codebase before they can contribute and the existing team stops building in order to teach them. Fred Brooks, who managed IBM's OS/360 software project, stated this in The Mythical Man-Month (Addison-Wesley) as Brooks's law: adding manpower to a late software project makes it later.
Software tasks depend on each other, so every extra person adds conversations and reviews. Extra people help when they are added early, to work that is clearly separate, such as a second platform or an independent module.
What parts of the timeline does the client control?
The client controls more of the schedule than most expect: decisions, feedback, content and access. Your developer cannot move faster than these arrive.
Decisions and feedback
Name one person who can approve work, and agree a turnaround for feedback. A design that waits a week for comments from five people, who then disagree, costs more than a week.
Content and access
Text, images and product data are usually the client's job. So are accounts: domain, hosting, payment provider, Apple Developer and Google Play, and credentials for any system being integrated. Start these on day one, because some providers verify your identity or business first.
How do I read a project plan?
Read a project plan for dependencies and assumptions, not for the end date alone. A plan that shows only a final date tells you nothing about what could move it. Check that it includes:
- Milestones tied to something you can see and use, such as a clickable design or a working login, not percentages.
- Your own tasks, with dates: content delivery, feedback rounds, account setup, acceptance testing.
- Named third-party dependencies and what happens if they are late.
- Time for testing, bug fixing and store review after development ends.
- Written assumptions, including what is out of scope and how a change request affects the date.
How can I shorten the timeline without cutting corners?
The honest way to launch sooner is to build less in the first release. List every feature, mark the ones a user cannot complete the main task without, and move the rest to a second release. A booking app, for example, needs search, booking and payment at launch; loyalty points and a referral program can follow.
Other honest savings are using an existing third-party service for payments, email or maps instead of building your own, and having content and accounts ready before development starts. Cutting testing is not a saving. It moves the delay to after launch.
What are the common mistakes that delay a project?
The most common mistake is starting development before the scope is written down, which turns every later conversation into a change request. Four others follow from it.
Treating content as a last step leaves a finished site with nothing in it. Leaving data migration to the final week hides problems until there is no time to fix them. Booking a launch event for the day development ends leaves no room for testing or store review. Adding features during the build without moving the date is the hardest to notice while it happens.
What should I do next if I am planning a project?
Before you ask anyone for a timeline, prepare the inputs that an estimate depends on. An estimate built on these is worth far more than one built on a one-line description.
- Write one page describing who the users are and the main tasks they must complete.
- Split features into first release and later.
- List every system the product must connect to and every source of existing data.
- Decide who approves work and how fast they will reply.
- Ask for a plan with milestones, client tasks and written assumptions, then compare estimates on those, not only on the end date.
Quick answers
How long does it take to build a website?
It depends on the number of page types, whether content is ready, and how many integrations are involved. A site with finished text and images and few integrations is the shortest kind of project, and no reliable figure can be given before the scope is written down.
How long does Apple App Store review take?
Apple states that App Review typically reviews at least 50% of submissions in less than 24 hours and 90% in less than 48 hours, as checked on October 6, 2026. Incomplete submissions can be delayed or may not pass.
How long does Google Play review take?
Google states that certain apps and developer accounts are subject to extended reviews of up to 7 days, or longer in exceptional cases, as checked on October 6, 2026.
Does adding more developers make a late project finish sooner?
Usually not. New people need time to learn the project, existing developers lose time teaching them, and coordination work grows with team size. This is known as Brooks's law.
What is the fastest honest way to launch sooner?
Reduce the first release to the features users cannot do without and ship the rest in later releases. Cutting testing or skipping scope definition moves the delay to after launch instead of removing it.
Conclusion
A website, web application or mobile app takes as long as its scope, its decisions and its outside dependencies require. Adding people late does not buy time back; a smaller first release does.
If you have a project in mind and want a timeline based on your actual scope, contact Entrant Technologies and we will take a look.