The App Development Process, Step by Step
Building a mobile app runs through the same stages whoever builds it: work out what the app is for, design it, build it in short cycles, test it, get it through the App Store and Google Play, release it, and keep it working. Here is what happens in each step and what you, the client, do.
The store facts here come from Apple's App Review page, TestFlight page and phased release help, and from Google's Play Console Help on testing tracks, testing requirements for new personal accounts and staged rollouts. Timelines and advice marked as our view are how we run projects, not a rule.
1. Discovery and scope
Discovery answers three questions: who will use the app, what they need to get done, and whether an app is the right answer at all. (Our mobile app vs web app guide covers that last one, and what a PWA is explains the middle option.) Then the first version is scoped: the smallest set of features that makes the app useful on its own. Our MVP guide shows how to cut a scope down.
What you do: explain the business goal, name the users, share any existing systems the app must talk to (a booking system, a shop, a CRM), and decide what is in and out of version one. A written brief helps; the project brief guide lists what to put in it. This is also when the budget gets real, and app development cost explains what drives it.
2. Design and prototype
The key screens are designed and linked into a clickable prototype you can try on your own phone before any real code exists. Changing a screen at this stage takes hours; changing it after it is built takes days. Design also covers the easily forgotten flows: sign-up, empty screens, errors, no connection.
What you do: click through the prototype on a real phone, show it to a few people who match your users, and give feedback in one round per version. Send brand assets and real content.
3. Build in sprints
The build covers more than the screens: an app usually needs an API, a database and an admin dashboard where your team manages content and users. The technology is chosen here; our React Native vs Flutter guide compares the two common ways to build for iPhone and Android from one codebase. The work runs in short cycles (sprints), each ending with a test build installed on your devices, so you see progress every couple of weeks instead of all at once at the end.
What you do: install each test build, try it, and send feedback with screenshots. Keep new ideas on a list for the next version; adding them mid-sprint is how launch dates slip. Set up the Apple and Google developer accounts in your business's name early, since store testing needs them.
4. Testing
Testing runs through the build, not only at the end: on a range of real iPhone and Android devices and screen sizes, on slow connections, and through every flow from install to account deletion. Both stores have tools for testing with real people before release. Apple's TestFlight lets you "designate up to 100 members of your development team" as internal testers and "invite up to 10,000 external testers". Google Play offers internal, closed and open testing tracks; an internal test goes "to up to 100 testers for initial quality assurance checks". Our mobile app testing guide covers what to test and how.
What you do: recruit a handful of real users as testers and use the app as they would. If the Play account is a new personal account rather than an organization account, plan for Google's rule that such developers "must run a closed test for their app with a minimum of 12 testers who have been opted in continuously for at least 14 days" before they can apply for production access.
5. Store submission
Both stores review apps before they appear. Apple says it reviews "all apps, app updates, app bundles, in-app purchases, and in-app events" submitted to App Store Connect, and that "over 40% of unresolved issues are related to guideline 2.1: App Completeness, which covers crashes, placeholder content, incomplete information, and more." Submission means store listings, screenshots, a privacy policy, privacy declarations and, for Apple, a demo account for any login. Our guide to publishing on the App Store and Google Play walks through each part, and app store review rejections covers the common reasons and how to respond.
What you do: approve the listing text and screenshots, publish the privacy policy on your website, answer the data-collection questions accurately, and leave room in the launch date for a rejection and a resubmission.
6. Launch and rollout
The first version goes live in full; the stores' gradual tools are for updates. Google says "staged rollouts can only be used for app updates, not when publishing an app for the first time"; with one, "your update reaches only a percentage of your users, which you can increase over time." Apple's phased release spreads an automatic update "over a 7-day period", and you "may pause the release for up to 30 days". Our app release rollouts guide covers when to use them and what to watch. In the first days, check the crash reports in Play Console, Xcode and any crash tool; our guide to app crash reporting shows where to find them.
What you do: tell your customers the app exists (email, website, in your shop), watch the first reviews and support messages, and decide with us which fixes go into the first update.
7. Maintenance
An app is never finished. Apple and Google release new operating system versions every year and raise their store requirements over time, so an app that is never updated eventually stops working well or stops being accepted. Our mobile app maintenance guide covers what that involves and how to budget for it.
What you do: keep the developer accounts and their payments current, keep the code and accounts in your business's name, and plan small regular updates.
How long it takes
Our view, for a typical first version of a business app: discovery and design take a few weeks, the build takes a few months, and testing and store submission add a few more weeks on top. A simple app with a handful of screens can be quicker; payments, real-time features, many user roles or links to existing systems make it longer. The usual causes of delay are late feedback, scope added mid-build and content that arrives at the end, and you control all three.
If you want help running these steps, see our mobile app development service; we follow this process from discovery to after launch.
Frequently asked questions
What are the stages of app development?
Discovery and scope, design and prototype, build, testing, store submission, launch, and maintenance. Testing overlaps the build, and maintenance runs for as long as the app is live.
Can I skip the prototype and go straight to building?
You can, but changes found after building cost far more than changes found in a prototype, and for a small app the prototype can be a few linked screens.
Do I need my own Apple and Google developer accounts?
We recommend it. Accounts in your business's name mean the listing, its reviews and its users belong to you, and another team can take over later if needed.