How long does it take to build an app? A UK timeline

A typical small business app takes three to six months from the first conversation to being live in the App Store and Google Play. Roughly a month goes on scoping and design, two to four months on the build, and two to four weeks on store setup, testing and review. The store steps are often forgotten, and since Google added a 14 day closed test for new personal accounts, they can move a launch date on their own.

How long does it take to build an app in the UK?

Building an app in the UK usually takes three to six months for a focused first version, and longer when the app needs payments, user accounts, integrations with other systems or an admin dashboard. Those ranges are a planning guide rather than a promise, because the honest answer depends on scope more than on anything else.

The phases look like this for a typical small business app:

1. Discovery and scoping: one to three weeks.
2. Design: two to four weeks.
3. Build: eight to sixteen weeks.
4. Testing and fixes: two to four weeks, overlapping the end of the build.
5. Store setup and review: two to four weeks, some of which can run in parallel.

If you have read our guide to what an app costs in the UK , the same decisions drive both numbers. Every feature you cut from the first version saves time as well as money.

What happens in the first month?

The first month of an app project is mostly decisions, not code. Discovery turns an idea into a written scope: who the users are, what they need to do, which features are in the first release and which wait.

Design follows. A designer turns the scope into screens you can click through on your own phone before anyone writes the real thing. Changing a screen at this stage costs an afternoon. Changing it after the build costs a week.

Two jobs belong in this first month that many people leave until the end:

• Open your developer accounts. Both stores take time to verify a business, covered in detail below.
• Write down what data you collect. Apple and Google both ask for a privacy policy and a description of the data your app handles, and the answers shape the build.

How long does the build itself take?

The build itself usually takes two to four months for a focused first version. A simple app with a handful of screens and no accounts sits at the short end. An app with logins, payments, notifications and a dashboard for your team sits at the long end, or beyond it.

The things that stretch a build are predictable:

• Integrations. Connecting to a booking system, a stock system or an accounting package depends on someone else's software and documentation.
• Payments. Taking money inside an app brings store rules, refunds and receipts with it.
• Changes of mind. New ideas mid build are normal. Each one should go on a list for version two unless it is essential.
• Slow feedback. If a question waits a week for an answer, the project waits a week too.

Building for iPhone and Android at the same time from one shared codebase, which is how most small business apps are made today, keeps this phase close to the length of building for one platform. A good team will show you working builds on your phone every week or two, so you see progress rather than hearing about it.

Why the app stores add weeks to your launch

The app stores add weeks because both of them check who you are, and Google checks that your app has been tested by real people. None of this is hard, but none of it can be rushed, and it is the most common reason a finished app misses its launch date.

Google Play's 14 day closed test

Google Play requires personal developer accounts created after 13 November 2023 to run a closed test before they can publish. At least 12 testers must be opted in, and they must have stayed opted in for the previous 14 days in a row. Only then can you apply for production access, and Google says that review "usually takes seven days or less".

So on a personal account, the minimum gap between a testable Android build and a public listing is about three weeks, and longer if testers drop out or barely use the app. Finding 12 real people who will install a test version and keep it is a job in itself. Staff, friends and loyal customers are the usual answer.

Organisation accounts and the DUNS number

A business can register an organisation account on Google Play instead, and Google describes these accounts as the right choice for commercial activity. The 12 tester rule in Google's help page is written for new personal accounts. To create an organisation account you need a DUNS number, a free nine digit business identifier issued by Dun and Bradstreet.

Apple asks for the same thing. To enrol as an organisation your business must be a legal entity with a DUNS number, a working website on its own domain and a work email address on that domain. Apple's help pages say to allow up to five business days to receive a new DUNS number, then up to two more business days before Apple can see it. Apple's programme costs 99 US dollars a year.

This is also where you decide who owns the accounts. They should be registered to your business, with the agency added as a user, as we explained when publishing an app got stricter in 2026 .

Apple App Review

Apple's own figures say App Review handles at least 50% of submissions within 24 hours and 90% within 48 hours . The delay comes from rejections rather than the queue. Apple says over 40% of unresolved issues fall under its App Completeness guideline: crashes, placeholder content, broken links and missing login details for the reviewer.

Google can be slower on a first release. Its help page on publishing your app warns that some apps get extended reviews of "up to 7 days or longer in exceptional cases".

What a realistic launch plan looks like

A realistic plan works backwards from the date you want to be live and puts the admin early. For a launch in spring 2027, that means starting in the autumn.

1. Week one: request DUNS numbers if you do not have them, and decide who owns the store accounts.
2. Weeks two to six: scope and design, with developer accounts opened and verified in the background.
3. Weeks six to twenty: the build, with a test version on real phones as early as possible.
4. Final four weeks: closed testing, fixes, store listings, screenshots, the privacy policy and submission.
5. Launch: a week or two of slack after approval, so a rejection does not move your announcement.

Apple lets you request an expedited review for a critical bug or a dated event you are directly involved in. Treat that as a safety net, not a plan.

How to make an app take less time

The fastest way to shorten an app timeline is to shrink the first version. Pick the one job the app must do well, launch that, and learn from real users before building the rest.

The other savings are practical. Answer questions quickly, name one person who can make decisions, start the store accounts in week one, and line up your testers before the build finishes. Not every idea needs an app at all. Sometimes a web app that works in any browser gets you there sooner and skips the stores entirely.

Our mobile app development work covers the whole journey, and we have taken our own apps, Spello and Jude, through both stores, along with Freeater for a client.

If you have a launch date in mind and want an honest view of whether it is realistic, book a free 15 minute call .

Frequently asked questions

Can an app be built in a month?

A very small app with a few screens and no accounts can be built in a month. Getting it into both stores usually adds another two to four weeks for accounts, testing and review. Most business apps need more than a month once logins, payments or integrations are involved.

Do I need 12 testers to publish on Google Play?

Only if you publish from a personal developer account created after 13 November 2023. Those accounts must run a closed test with at least 12 testers for 14 days in a row before applying for production access. Businesses usually register an organisation account instead, which needs a DUNS number.

How long does Apple take to approve an app?

Apple says it reviews at least half of submissions within 24 hours and 90% within 48 hours. A rejection restarts the clock once you resubmit, so allow a few extra days for a first release.

Is it quicker to build for iPhone or Android first?

Building for both at once from a shared codebase usually takes little longer than building for one. If you do launch on one platform first, the Apple route often reaches the store sooner for a new personal account, because Google adds its 14 day closed test.