How do you develop and test your own apps for different smartphone operating systems?

Hardware based apps should develop as Native one which helps developers to integrate all 3rd party Api's and performancr will better. If it is an content oriented or e-commerce apps blindly we can go for Cross-platform such as flutter or react native

Choosing a cross-platform framework is a compelling option for most app projects today. Even when native languages like Swift or Kotlin are needed for specific extensions, cross-platform solutions offer faster development cycles and cost savings. While performance concerns have existed, technological advances are narrowing the gap. Take React Native's FABRIC architecture as an example. It replaces the traditional bridge with an efficient C++ communication interface, achieving near-native performance. This results in a smooth UI at 60 FPS and synchronous communication with native components, making cross-platform an increasingly intelligent choice for both speed and efficiency.

A major advantage of cross-platform development is that there is less code to manage and it is mostly written in one programming language this reduces overhead significantly as a single code base is used for both iOS and Android apps.

Websites are a lot cheaper to build & maintain, so the first question to ask is whether you really need an app. For mobile development, cross-platform frameworks like Flutter, MAUI/Xamarin, and React Native/Expo are widely known, but it's vital to recognize the remarkable advancements in Apple's iOS and Google's Android. Apple's SwiftUI enables unified native app development across all Apple platforms—TV, Watch, MacBook, iPhone, iPad, and Vision Pro. On the Android side, Jetpack Compose, reminiscent of SwiftUI's declarative UI, is Google's recommended approach for native UI development. Tools like Figma extensions simplify the conversion of designs to SwiftUI or Jetpack Compose code, bridging the gap between design and development.

The choice in platform could be based primarily on requirements and then on available technical resources. Both of them lead to trade-off which need to be agreed to select the best suited candidate. An example: if performance requirements are prioritized it doesn't necessarily means native is the way to go since optimization performed by the technical team could provide better performance.

For cross platform Development visual studio code is recommended. It includes plugin for all like (Git, command terminal) etc

When developing with flutter, the preferred IDE is VS Code. The only drawback is that migration from VS Code to Android Studio is difficult and not documented.

If you intend to develop cross-platform Android Studio and Xcode should be installed and I would recommend using a Macbook majorly because of the ios development. For React native developers you can start out using expo cli for development. This significantly reduces the setup time required to start building an app, and you can move to react native cli when you are a bit more comfortable with react native.

Building iPhone apps differs from Android in several ways. iOS development typically necessitates the latest Xcode version, which, in turn, demands the most recent macOS – adding to the cost. Even used MacBooks with supported OS versions, tend to be pricier than brand new Windows PCs. Adequate app testing often requires a physical iPhone, further increasing expenses. This high monetary barrier, exacerbated by hefty taxes (>100%) in some regions like Brazil, limits indie developers. Additionally, iOS publishing costs $100/yr compared to Android's one-time $25 fee. However, it's worth noting that Apple users tend to spend more money on apps statistically, making iOS development potentially lucrative if you achieve product market fit.

To develop an app using react native, you would need to learn the fundamentals of JavaScript, It helps to have prior knowledge of React but it is not compulsory. Some of the most important concepts to learn in react native are 1) Jsx and css 2) components 3)state management 4) npm modules 5) expo bare workflow, expo managed workflow, and react native development and the pros and cons of all three workflows. just to mention a few.

If you are new to mobile development, try to choose a language more similar to your current stack. If you are beginner in development in general, you can start with Kotlin or React-Native(js in general)

OOPS will be major base for all language. Going through basics will help. Learn the advanced functionalities that handles the background services will be helpfull

If there's no 3rd party libraries or rarely used native features that you are dependent on for your core functionality, you can use cross platform frameworks. Most of those frameworks work fine for apps that perform basic functionality-fill information, upload picture, submit form (99% of apps). If it's a basic app, just stick to what language programming skills is available in the company: - If C# devs are available, use MAUI/Xamarin - For JS/TS/React devs you can use ReactNative - For someone willing to learn anything new, you can use Flutter If the app is not basic, use what is recommended by Apple-SwiftUI & Google-JetpackCompose

Deciding on the "functionality" of the app needs to be done from the start, not as the fourth step like described in this AI article. The functionality is going to determine the development environment, not the other way around.

As mentioned above, each mobile OS has it's own design guidelines, so do not fear to make your Android and IOS apps look a bit different.

Use wireframe software for your relevant devices that you plan to deploy your app or website to. For example, Balsamiq. It will allow you to gather more input from potential users early on in the pre-development phase on the UI and even the core proposition of your app or website. Additionally, it can provide a more solid reference for the Dev team...less guesswork.

when it comes to app design one of the major things to be aware of is the difference between responsive dimensions and fixed dimensions. I typically would recommend using responsive dimensions for texts and fixed dimensions for shapes

Do some benchmarks, look for other similar apps and extract what they’re doing great and try to avoid theirs mistakes. You can also find some prototypes on Figma community for free and use to create a MVP or get some ideas.

Before you dive into coding the app, it is strongly recommend to create a working prototype using a tool like Figma, so you can perform some customer research & usability testing, and reiterate, in order to better achieve "product market fit". The prototype can help you create a marketing video which should be sufficient for getting investments from pre-seed investors like Tech Accelerators. From all the 50+ apps I have built, I have experienced that it's too risky to build first without a signed up customer, since your first few sales are the toughest, and you will likely need to fundamentally change your product several times, regardless of how game-changing your initial idea might be.

It’s important to have in mind the key objectives of your app, defined patterns and architecture you will use, what will be tested and so on…