Although the Apple Store has witnessed a total of 180 billion iOS app downloads (as of June 2017), some findings show that 24% of iOS users uninstall an app after just one usage thus your mobile application must provide an outstanding performance to avoid getting lost among thousands of apps flooding the Store each day.
The reason why Apple is widely used in enterprises and businesses is because they pay strong attention to security and intuitive UI.
Here are some best practices to consider when building iOS applications.
Stage I - Research
First, decide whether you want native iOS app or a cross platform development. Even if you decide to proceed with cross like Xamarin, you will need to know iOS basics to build an app that is functional and consistent to the platform.
Once decided for native iOS, the next step should include proving the business case of your mobile app.
Here, you should identify your target audience, research and define your User Persona(s), create a mobile app specification and weigh the costs and benefits.
Once you’ve done groundwork for the development, you can move to more technical preparations.
Stage II - Setup and Tech Fundamentals
iOS is well known for its strict policies and formal UI/UX practices as UI deployment affects the app performance and the overall mobile experience
Prior to writing any line of code, make sure that you have a good iOS development team which understands and follows the guidelines provided by Apple.
Regarding the languages, Swift programming language offers a number of neat features while its usage increased among developers. Back in 2016, stats showed a clear domination of Objective C over Swift, which was used in only 11% of App’s Store Top 100 apps. Nowadays, the situation changed as Swift is also convenient for complex projects whilst its code is more readable, modern and quicker.
Objective-C is also a great choice, where you can use the language itself or some of its elements, like libraries in a proper mix of both (Swift and Objective-C), taking the best of each language.
Another important aspect is Xcode – it is an IDE provided by Apple to provide native integration level and proper tooling to build iOS apps. We use Xcode as it is free and it is Apple’s product. There are other alternatives like AppCode with add-ons to facilitate the development, however check its pricing models. Take all pros and cons and decide which one would be the best for your mobile app development.
You should always pay attention to choose the proper version – as new iOS versions are released each year, older platforms become outdated quickly. Although older platforms may be compatible, it would make more sense to focus on the newest versions and develop your mobile app to be completely future ready.
The iOS system of devices is quite rich and choosing the right target device should depend on your mobile app’s purpose – nowadays, there is a standard practice of building universal apps which adjust to the screen. For more value, you can adapt your app to run on Apple Watch which would be a great add-on for a health monitoring tool.
Regarding the coding style, you should make sure all team members are consistent in coding throughout the development process. Such an approach will make it easy for the team members (or external colleagues) to read or improve the code.
You can establish solid coding standards or choose from existing ones like GitHub, Objective-C or Swift guidelines. Google’s Objective-C guide helps to create an app which is easy to maintain and upscale.
Another important aspect is proper architecture being the foundation for building a well structured app – while there are a couple of architecture design approaches, the most commonly used in iOS is the Model-View-Controller (MVC) pattern and it is the recommended one by Apple. This pattern divides the code into objects, designating each of them one of 3 main functions (view, model, controller), however developers combine the MVC patterns with other options for better results, like Model-View-ViewModel (MVVM).
The Zesium iOS team would also add a Model-View-Presenter (MVP) pattern as we usually use it for most of the projects in our team.
Stage III - Engineering process and tools
When writing clear and high quality code, the important aspects are the naming principles.
When naming methods, classes and other code elements, always follow Apple’s basic guidelines by keeping the names clear and avoiding abbreviations or any kind of ambiguity.
Naming principles should be consistent throughout the process, keeping its source files to build a clear and maintainable code. A good idea can be to set some common folder structure to help the naming consistency across the project. The structure can include folders like Models, Views, Controllers, Stores, etc.
iOS offers a great number of libraries and frameworks which can be used to solve certain issues, from UI implementation to compatibility with device hardware. Those third-party tools can reduce the amount of time and cost of building the same features from scratch.
iOS platform has always been considered as ‘closed’ due to its restrictions, yet they provide an abundance of open source projects for you to use. When Swift was released as an open source, Apple has shifted its strategy allowing developers to contribute to the language and create more accessible tools. It is a good practice to use such third-party tools – there are many resources lists and dozens of such libraries so no need to make more work for yourself than you need.
However, even with consistent coding style and common practices, there is no ‘one’ way to develop software. Each team member relies on experience and knowledge when writing lines of code but fostering code review can have a positive impact on the code quality and the quality of the app in general. IBM resource for developers provides some standard practices that can help achieve better results.
Always make sure to focus on well implemented UI like iOS does and follow the event driven programming – it presupposes that specific events, triggered by some actions or outputs, determine the flow of the app. Apps built with event driven programming carry certain benefits for a business, like automated workflow, improved communication and more.
Addition to this is Object-Oriented Programming (OOP) – using objects as key units for building software. Simply put, decomposing complex software into smaller pieces to be easier to develop and maintain. Good use of OOP will enable you to maximize the code reuse and minimize the maintenance costs.
When dealing with complex projects, developers often need to deal with project-specific problems with innovative solutions and concepts. Providing enough time for research can result in significant savings in the longs run. Thorough preparation and working on the product concept is better than finding out the product cannot be implemented as planned after you’ve already commenced.
Continuous Integration and Continuous delivery (CI) is another important element representing standard practice in software development (not only mob apps) and being the integral part of agile development.
It can be implemented by several tools like Jenkins CI, Bitrise, Greenhouse CI, CircleCI etc. which deploy various methods to the CI process but have one thing in common: help you to build code for different environments, automate tests, manage defect logs, deliver artifacts and more.
Don’t forget to figure in battery consumption – an experienced iOS development company also knows the expectations of the users. Battery consumption and life are the most important issue for smartphone users and only the apps that do not affect the battery negatively will be retained.
It makes sense as high-performance processors consume more power resulting in low battery levels in a short time – this is one of the main reasons for the great dissatisfaction among users of their apps.
Include some measures to reduce battery consumption to get an advantage over your competitors and always test your app before you launch it.
Stage IV - Deployment
Prior to reaching the launch stage of your iOS app, consider getting the Apple required certificates and accounts in advance.
If you are the app owner, create your Apple developer account (around $100 a year), and give permissions to your iOS development team to create certificates and build the app on your own account. Each developer gets an access (admin or developer) to the app owner’s account and prepares the groundwork to commence the development.
The best way to ensure a more efficient start is to obtain such accounts and certificates prior to starting a development process.
Once your app is ready to open its door, it is important to decide how you will distribute it. Apple currently offers 3 distribution models:
- App Store – commonly used model for direct upload to be available for iOS users. You can set parameters like target country, supported device or versions.
- TestFlight service – it is in scope of the App Store (meaning you upload the build on the Store) and provides an option to beta-test the app build before launching. You can have 100 internal testers (connected to the Apple account through a certain role, e.g. admin, developer etc.) and 10000 external users (full name and email).
- iOS Developer Enterprise Program is a program for enterprise level or business apps – although a costly solution, it provides complete privacy making it secure for your employees and contractors.
Before submitting your mobile app to an App Store, ensure that your app is properly configured for release – besides certain forms to complete and files to submit, Apple performs a manual review to verify all apps referred to their store.
Regular monitoring of App Store ratings and reviews are important for a new app – try to engage with reviewers and help the disappointed ones as it will improve your online reputation in the long run.
Stage V - Security
Always focus on security!
Some industries demand a high level of security like fintech, healthcare or internal enterprise apps dealing with sensitive private and business data – if you want your iOS app to be considered as a serious professional, you must implement the best security practices.
Basically, it is impossible to create 100% protection from data theft unless you don’t store data at all – the best way is to follow the legitimate Secure Coding Guide by Apple or deploy some of the best practices like custom encryption, data protection etc.
When talking from the user’s point of view, there are also some good practices to protect your own privacy with iOS 14.
Stage VI - Business-wise
Once your app is launched, the work is not over – you should implement analytics and reporting tools to see how your users interact with your app or why they uninstall the app. This provides valuable insight to help you improve your app later, where some of the popular tools are:
On a global scale, the iOS app downloads number has been steadily rising since 2016 up to the 2Q of 2020 with 9.1 billions of downloads.
You can, e.g. develop a free product with in-app purchases to ensure steady revenue – in-app options should be simple and offer value with the basic version. Not all types of apps suit such a monetization model so be careful and check other monetization methods to decide which one suits your mobile app the best.
If you plan to make your app for the global market, consider the app internalization to make it able to adapt to various languages. Preparing the app for localization requires a number of certain steps like separating language from the rest of the user interface, exporting user-facing text by Xcode and more.
Be extra careful with right-to-left languages such as Arabic, as they require mirroring the UI and changing the text direction.
Keep in mind that in software/mobile development, the product is never completely finished and even though you’ve implemented most of the planned features, the time will come to review the old features, possibly remove some of them and eventually add new features.
When Apple introduced an evaluation process ‘to ensure that apps available on the Store are functional and up-to-date’, an app is not allowed to sit around with no updates but it keeps the market competitive and relevant for users although setting additional duties on the app developers.
If you’re developing an iOS mobile app, a good place to rely on is Apple developer resources website.
The common saying is that iOS apps bring less worries about your own privacy. That does not mean that Apple users are totally protected from malware issues, but that those are rare cases, as per MacWorld UK.
Even though Apple is famous for their restrictions and strict policies, they provide a solid approach to providing developer resources and tools.
Make sure to use these tools to your advantage and build a solid and functional iOS app.