The ultimate guide to iOS app development

10 min read
June 15, 2023

Have you heard of the 9-year-old Indian girl that developed a full-blown iOS app that was praised by none other than Apple CEO Tim Cook?

It’s certainly one of the most inspiring stories we’ve ever encountered.

It also proves that anyone can develop an iOS app with the right tools, methods, and approaches.

And this ultimate guide to iOS app development will show you the ropes!

How much does it cost to develop an iOS app?

The costs of developing an app can vary widely.

At the low end, it could cost around $40,000 for a simple app with basic features.

A more complex project with custom graphics, extensive UI, and advanced features can easily cost $100,000 or more.

But these are just ballpark figures, at best. That’s because estimating the cost of an iOS app is notoriously difficult and unpredictable.

Indeed, from the time you predict the project cost at the beginning until you launch the app, the price difference can be as high as 400%.

How to accurately estimate cost for building digital products

Source: Praxent

This discrepancy is partly due to the numerous factors that can impact app costs.

We’ve already touched on the first one—complexity. The more features, UI elements, and components an app has, the more work it will require. Therefore, it would be more expensive.

Your development team will also affect your costs.

Unsurprisingly, the more complex project would require a bigger team with more expertise. If you need specialized skills like blockchain or finance, that could set you back even more.

But your team’s location also plays a role.

As you can see below, developer salaries vary widely worldwide. A senior developer in Croatia could typically charge half of his North American counterpart.

Thus, if you outsource your development to these countries, your costs could drop dramatically.

Software Project Development Prices

Source: Soject

Another thing that could affect costs is your tech stack. Some third-party tools and plug-ins require payment and, in some cases, specifically hiring someone skilled in using them.

These will add more to your expenses.

Finally, additional tasks beyond development, such as integrations and data migrations, also need extra time, effort, and money.

What languages to use for iOS app development

Let’s look at two of the primary languages used for creating iOS apps—Swift and Objective-C.


Swift is currently the official language for iOS app development, having replaced Objective-C.

This is no accident. Apple intended this, which is why they made Swift one of the easiest programming languages to learn ever.

It’s largely thanks to Swift’s syntax that closely resembles human language. As a result, people can understand it much faster.

Swift code is also easier to edit, debug, and maintain due to this advantage.

Swift also has the performance to match its user-friendliness.

According to Apple’s research, Swift code runs up to 4.29 times faster than Objective-C and 8.4 times faster than Python.

objective c vs swift speed test

Source: Altamira

Apart from speed, Swift also has stable performance.

It has automatic memory management that prevents memory leak issues, so developers can focus more on coding.

Plus, Swift is more stringent when checking compile-time errors, thus reducing crashes in the final app.


While Swift is slowly outclassing Objective-C, the latter is by no means a dead language.

As the original iOS programming language, Objective-C is still relevant today. Its longevity has made it a mature and reliable language for iOS development.

This is especially true if you need to maintain older iOS apps. That’s because Objective-C is the only language compatible with all iOS versions.

In contrast, Swift only works for apps deployed in iOS 7 and above.

Objective-C also has a huge community backing it up. Thus, if you encounter any problems while coding, there are hundreds of developers you could ask.

Of course, Objective-C has its fair share of drawbacks.

These include a complex syntax, manual memory management (which makes it prone to coding errors), and a slightly slower performance than Swift.

What is the process of developing an iOS app

Developing an iOS app isn’t that different from creating software on other platforms like Android. Here are the steps involved.

Doing market research

How do you know if your app idea will be worth the thousands of hours and dollars to develop it?

Simple—you need to validate it with your end users through market research.

This is arguably the most critical step because it tells whether your app is solving a real problem your market has. If it isn’t doing that, no one will use it, and your app will fail.

One of the critical steps here is to understand your market more intimately. What are their biggest problems, preferences, and behaviors?

You can achieve this by gathering both demographic (quantitative, fact-based) and psychographic (qualitative, personality-based) data from your ideal prospects.

Here are their differences:

Demographic profile of a prospect

Source: Freshworks

There are myriad methods to get this information, such as interviews, questionnaires, focus group discussions, and secondary research.

The other thing you need to do is study your competitors.

Specifically, look at their successes and mistakes. The former so you can improve on them, and the latter so you can avoid them.

An easy, free, and non-invasive tactic is to look at the reviews on your competitors’ app store pages.

Figuring out the design

Your app’s design plays a major role in providing a great user experience (UX), which in turn helps make your app successful.

Consider that for every $1 you spend on improving your UX, you can get $100 back in returns—a 9,900% ROI.

Thus, app design should be given as much importance as functionality.

One of the best tools you have to achieve this is the wireframe.

wireframing tips

Source: Icons 8

A wireframe is a rough sketch of your app’s layout. It shows where the major UI elements are without going into detail.

The advantage of a sketch like that is that you can draw and share your ideas with others. This lets you get their input, revise as needed, and iterate through many versions.

Thus, you can get to the best version of your design rather quickly.

During the design phase, you should also determine your app’s architecture or how the internal components are arranged.


Source: DECODE

A good architecture makes your app more modular, helping you revise and maintain it much easier in the future.

Developing the iOS app

With your app idea and design validated, it’s time to put it all together during the development phase. Here, your developers will write the code and bring your vision to life.

This is a vital part of the process because it could ruin months of work if developers can’t translate your ideas properly into a working app.

Typically, development involves coding two parts—the front end and the back end.

Back end

Source: Packtub

The front end refers to coding the app itself, including the UI design and some support functions.

Typically, the important logic and algorithms aren’t processed here. Instead, they’re done by code on the web server. This is called the back end.

The back end also connects to a database to store and retrieve information.

The front and back end communicate and send data through application programming interfaces or API.

This separation makes development faster because the components can be created simultaneously. It also makes revising and maintaining the app easier.

Performing app testing

During and after development, the app must be tested thoroughly to ensure that the app functions as expected with as few bugs as possible.

This phase requires multiple test methods to check different aspects of your app.

For example, integration testing verifies if different app components are working well together. In contrast, load testing checks how many concurrent users the system can handle before failure.

Testing is a complicated process because so many components need to be evaluated. So to ensure complete coverage, you need to plan your testing phase systematically.

This can be achieved through the software testing life cycle (STLC).

software testing cycle

Source: Syndicode

An STLC forces you to determine your app’s test cases, environment, and methods for running quality assurance. Nothing is left to chance.

Your STLC will also help you determine when and where to use automated testing tools.

Automation helps speed up your tests and keep them consistent. However, they can’t be used for qualitative tests that require subjective answers, such as usability testing.

Deploying the iOS app

Once the app is completed and fully tested, the last step is to deploy it on the Apple App Store.

However, it’s not that straightforward.

Before publishing your app, it must meet Apple’s safety, performance, business, design, and legal requirements.

The problem is that Apple is notoriously strict with this process, and apps are consistently rejected.

To avoid this, the development team must review the App Store Review Guidelines and ensure the app complies with them. If not, adjustments should be made until the requirements are met.

And when the app is published, don’t forget to consider app store optimization (ASO) strategies. These can help make your app more visible, leading to more downloads.

Why consider outsourcing iOS app development

As you can see, iOS development is relatively straightforward. But it can also be costly and challenging, especially if you don’t have an experienced team.

A good alternative is to simply outsource development to a third-party agency. There are several benefits to this.

We’ve already touched on the first one—cost savings.

As we mentioned, outsourcing can help you save money because you can get exceptional talent at a lower cost if you pick the right country.

Outsourcing also helps avoid startup costs and time.

There’s no need to hire developers individually or invest in equipment, as an outsourced team will already have everything that’s needed.

Plus, you also get to tap into expertise unavailable in your region. For instance, you can hire the best financial expert halfway across the world.

Now, that’s not to say outsourcing is easy. There are huge challenges that you need to go through, some of which are listed below:

software outsourcing

Source: Mobindustry

But that’s exactly why we think Croatia is one of the best places to outsource today.

Apart from lower costs that give great value for money, Croatia also boasts one of the biggest talent pools in the region.

Developers also have high English proficiency and a working culture familiar to Westerners.

In other words, hiring a Croatian development agency can help you reap the benefits of cost efficiency and exceptional talent while minimizing language and cultural barriers.

And if you’re considering partnering with an iOS development agency in the country, DECODE is a great choice.

We’ve developed dozens of successful iOS app projects in niches from finance to communication. That proves we have the experience and expertise to tackle your project.

But more than our skills, it’s our service that sets us apart.

Working with DECODE is just like having your own in-house team. All developers assigned to your project will work on it alone—no other clients competing for our time and attention.

And we insist on continuous communication, so you know exactly who’s doing what, when, why, and at what cost.

But don’t take our word for it.

Contact us today, and experience how DECODE can be the perfect partner to help you achieve app success!

Written by

Toni Vujevic

React Native Team Lead

Skilled in React Native, iOS and backend, Toni has a demonstrated knowledge of the information technology and services industry, with plenty of hands-on experience to back it up. He’s also an experienced Cloud engineer in Amazon Web Services (AWS), passionate about leveraging cloud technologies to improve the agility and efficiency of businesses. One of Toni’s most special traits is his talent for online shopping. In fact, our delivery guy is convinced that ‘Toni Vujević’ is a pseudonym for all DECODErs.

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