What you actually do to build a mobile app

Creating a mobile app means writing code that runs on phones or tablets, testing it until it works, and then putting it in a store where people can read it. The process has five main stages: deciding what your app will do, designing how it looks, writing the code, testing for bugs, and submitting it to Apple's App Store or Google Play. Each stage takes time and money, and most people either learn to code themselves, hire developers, or use no-code tools that let you build without writing code at all.

The length of time depends on what your app does. A straightforward app with one or two features might take three to six months if you work alone. A complex app with many features, user accounts, and connections to other services can take a year or longer. The cost ranges from nothing (if you build it yourself and learn as you go) to tens of thousands of dollars (if you hire experienced developers).

Key Takeaways

  • You need to decide whether to code the app yourself, hire developers, or use a no-code platform — each path has different time and money costs.
  • The five stages are planning what the app does, designing the interface, writing code, testing for bugs, and submitting to the app store.
  • A straightforward app takes three to six months; complex apps take a year or more.
  • You will need to pay annual fees to Apple and Google to keep your app in their stores, even after launch.
  • Most apps fail because they solve a problem nobody has or because the creator runs out of money before launch.

Three ways to build: code it yourself, hire developers, or use no-code tools

Learning to code yourself takes the longest but costs the least money upfront. You would learn a programming language like Swift (for iPhone apps) or Kotlin (for Android apps), then write the code line by line. Online courses through Codecademy, freeCodeCamp, or Udemy teach the basics in a few months, but building a real app that people want to use takes much longer. Most people spend six months to two years learning before they can build something worth releasing.

Hiring developers is faster but expensive. A freelance developer in the United States charges $50 to $150 per hour; a development agency charges $100,000 to $500,000 for a complete app. You can find developers on Upwork, Toptal, or by asking other business owners for referrals. The risk is that you need to know enough about what you want to explain it clearly, or you will end up paying for something that does not match your vision.

No-code platforms let you build an app by clicking and dragging instead of writing code. Tools like Flutterflow, Bubble, or AppGyver have templates and pre-built pieces you snap together. They are faster and cheaper than hiring developers, but they have limits — you cannot build anything as complex as Instagram or Uber, and you are locked into that platform's rules. No-code is best for straightforward apps like a booking system, a directory, or a way to collect information from customers.

The five stages of building an app

Stage one: planning. Write down what your app does, who will use it, and what problem it solves. Sketch the screens on paper or in a tool like Figma. Talk to five to ten people who might use it and ask whether they would actually pay for it or use it regularly. This stage takes one to four weeks and costs nothing if you do it yourself.

Stage two: design. Create mockups — detailed pictures of what each screen looks like, where buttons go, what text says. Tools like Figma or Adobe XD let you build these mockups and share them with developers or test them with potential users. This stage takes two to six weeks. If you hire a designer, expect to pay $2,000 to $10,000.

Stage three: development. The developers (or you) write the actual code. This is the longest stage and takes two to six months depending on complexity. You will have regular check-ins to see progress and catch problems early.

Stage four: testing. You and a group of real people use the app and report bugs — things that crash, buttons that do not work, text that is cut off. The developers fix these bugs. This stage overlaps with development and takes four to eight weeks. Do not skip this; apps that launch with major bugs get bad reviews and get deleted.

Stage five: submission and launch. You submit your app to the Apple App Store and Google Play. Apple reviews it for about one week; Google usually approves within 24 hours. You pay Apple $99 per year to keep an app in their store; Google charges $25 once. After launch, you monitor reviews, fix bugs that users report, and add new features based on what people ask for.

What you need before you start coding

Before you write a single line of code, you need a clear answer to three questions: What does your app do that existing apps do not? Who will use it, and how many people do you think will read it in the first year? How will you make money — through ads, a monthly subscription, a one-time purchase, or something else?

You also need to decide which platform to build for first. iPhone apps reach people with money to spend; Android apps reach more people overall but people are less likely to pay. Many creators build for both, but that doubles the work. A practical choice is to build for iPhone first, launch, get feedback, and then build the Android version.

Finally, set a realistic budget and timeline. If you are learning to code, add six months to your estimate. If you are hiring developers, get quotes from at least three people and ask for references. If you are using a no-code platform, spend a week testing it with a straightforward prototype before you commit to building your whole app on it.

Common reasons apps fail before or after launch

The most common reason is that the creator did not talk to potential users before building. They spent months creating an app that solves a problem nobody actually has, or solves it in a way people do not want. Before you build, show your mockups to at least ten people who are not your friends and ask them honestly whether they would use it.

The second reason is running out of money. If you are hiring developers, the project takes longer than expected, costs more than expected, or both. Set aside 20 percent extra in your budget for surprises. If you are learning to code, you might run out of motivation before you finish. Join a community of other app builders — on Reddit, Discord, or local meetups — so you have people to talk to when you get stuck.

The third reason is launching with bugs or a confusing design. People read an app, it crashes, and they delete it. Spend time on testing and ask real people to try your app before you launch. Their feedback will catch problems you missed.

What happens after you launch

Launching is not the end; it is the beginning. After your app goes live, you will spend time reading reviews, fixing bugs that users report, and adding features people ask for. Most successful apps go through dozens of updates in their first year.

You will also need to market your app so people know it exists. This might mean posting on social media, writing a blog, asking friends to leave reviews, or paying for ads. Most apps get discovered through word of mouth or app store search, so having a clear name and description matters.

Keep in mind that you will pay annual fees to keep your app in the stores. If your app makes money, you will also pay a cut to Apple (30 percent) or Google (30 percent) on each purchase or subscription. Plan for these costs when you decide how to make money.

Frequently Asked Questions

How long does it take to learn to code well enough to build an app?

Most people spend three to six months learning the basics through online courses, then another six months to two years building their first real app. The timeline depends on how much time you spend each week and how complex your app is. Starting with a straightforward app — something with three to five screens and one main feature — helps you finish faster and learn more.

Can I build an app without knowing how to code?

Yes, using no-code platforms like Flutterflow, Bubble, or AppGyzer. These tools let you build straightforward to moderately complex apps by clicking and dragging. The trade-off is that you cannot build anything as advanced as a major social media app, and you are dependent on that platform staying in business and keeping its pricing reasonable.

How much does it cost to hire someone to build my app?

Freelance developers charge $50 to $150 per hour; a straightforward app might cost $5,000 to $20,000, and a complex one $100,000 to $500,000 or more. Get quotes from at least three developers and ask for examples of apps they have built. Cheaper is not always better — a developer who charges less might deliver lower quality or take much longer.

What is the difference between an iPhone app and an Android app?

iPhone apps are written in Swift; Android apps are written in Kotlin or Java. They are built separately, so you cannot write one app that works on both. Some tools like React Native or Flutter let you write code once and deploy to both platforms, but they have limitations. Most creators build for iPhone first because iPhone users are more likely to pay for apps.

Do I need to pay to put my app in the app store?

Yes. Apple charges $99 per year to keep an app in the App Store. Google charges $25 once to put an app in Google Play, then it stays there as long as you keep it updated. If your app makes money through purchases or subscriptions, Apple and Google each take 30 percent of the revenue.