How long does it take
to build an app?

These match the timelines in our app development cost guide. The ranges are wide because scope varies more than anything else; the bottom of each range assumes decisions get made within a day or two.

Writing code is usually about half the calendar. The rest is everything around it.

Design and development can overlap — developers start on the backend and the screens already approved — which is how good teams compress a schedule without cutting corners.

Store approval is short but unpredictable, and it is the most common reason a launch date slips at the last minute.

• Apple says App Review typically reviews at least 50% of submissions in under 24 hours and 90% in under 48 hours¹. A rejection resets the clock after you fix and resubmit.
• Google Play says processing can take a few hours or up to seven days, longer in exceptional cases, and recommends at least a week's buffer between submitting and going live².
• New Google Play personal accounts must run a closed test with at least 12 testers who stay opted in for 14 continuous days before they can even apply for production access³. If you discover this in the last week, your launch moves by three.

There is also a trap in the obvious fix. Adding developers to a late project tends to make it later, because new people need onboarding and coordination grows faster than output — an observation Fred Brooks made in 1975 that still holds⁴. When a project is late, cut scope.

And watch the opposite problem. Work expands to fill the time available — Parkinson's law — so a generous deadline with a loose scope rarely finishes early.

1. Fix the date, flex the scope. Agree the launch date and a ranked feature list; anything that does not fit moves to version two.
2. Do discovery first. One to two weeks of user interviews prevents months of building the wrong thing.
3. Test a clickable prototype before development. Changing a Figma screen takes minutes; changing a built screen takes days.
4. Build cross-platform unless you have a clear reason not to — one codebase for Android and iOS.
5. Use proven services for login, payments, chat, analytics and push instead of building them.
6. Make one person the decision-maker, with a 48-hour answer rule.
7. Test continuously, on real low-cost Android phones as well as flagship devices.
8. Start store setup early — developer accounts, closed testing, privacy declarations and listings.

The timelines are Science of Apps editorial estimates for a first version built by an Indian agency or experienced freelance team, consistent with our app development cost guide. Store timings come from Apple¹ and Google's own documentation²³. We review them every six months.

MVP — the smallest version of a product that delivers its core value to real users. Sprint — a fixed work period, usually two weeks, ending in a demo. Closed testing — a Google Play track that shares a build with a chosen group of testers before public release. Staged rollout — releasing an update to a percentage of users first. Scope creep — uncontrolled additions to a project after it starts.