How do you ensure your Mobile apps work on all operating systems?

Mobile devices primarily operate on two ecosystems: Android and iOS. Developers can opt for native development using specific languages for each platform (like Kotlin for Android and Swift for iOS) or choose hybrid development with platforms like Xamarin or Flutter. The choice between native and hybrid largely depends on the product's requirements. If the app needs to heavily interact with hardware or perform CPU-intensive tasks, native development with Kotlin for Android or Swift for iOS might be more suitable. On the other hand, for apps primarily driven by APIs or UI interactions, hybrid platforms like Flutter could be a more efficient choice.

There are mainly two ecosystems to consider: iOS and Android. Unless your app specifically targets developing markets where iOS penetration may still be quite low, you really need to offer the best experience on both platforms. Web Apps and hybrid cross platforms apps (Xamarin, React) are flexible and cheaper to develop but often compromise on the sleekness and fluidity of the overall UX. Flutter has started to fill that gap and offers a decent cross platform solution with "native-like" results. That being said, for the very best experience, and for your iOS app to feel like an iOS app while the Android version feels familiar to Android users, I believe that you should go native, fine tune the UI for each platform, and code it twice.

One thing I've found helpful when deciding on the approach for developing a mobile app is to carefully evaluate the target audience and their preferences. Understanding whether your users are more inclined towards native app experiences, are comfortable with browser-based interactions, or are open to hybrid functionality can greatly influence your decision. By aligning the development approach with user expectations, you can enhance user satisfaction and adoption rates.

You need to understand that choosing a technology for development is just a small part of the entire product development process. You need to define a requirement management mechanism that is optimized for all your platforms. You need to determine approaches to verify the compliance of logic across all your platforms. This way, when developing a new feature, you will need to plan requirements and testing approaches in advance for all platforms.

New kid on the block is KMP. It combines best of both worlds. Code sharing and native UI. With this approach you can reduce development time and costs without the need to sacrifice preformance.

Actually, I disagree with the assumption that using cross-platform frameworks inevitably leads to performance trade-offs. While it's true that some frameworks might introduce a layer of abstraction that could impact performance, modern cross-platform frameworks like Flutter have made impressive strides in terms of performance optimization. By taking advantage of hardware-accelerated graphics and efficient rendering, they can achieve native-like performance that often rivals or even surpasses native development.

For the vast majority of apps, performance trade-offs are going to be negligible when using cross-platform frameworks, particularly given their backing by major players, and the common goal of improving the frameworks open source nature projects strive for. You could also argue maintenance costs are offset by the fact you have a collective of developers on one project, rather than across iOS and Android. If there are to be any challenges, it's often the fact that something like Flutter 'out of the box' is Material, and therefore styled like Android, which iOS users will find unintuitive.

Actually, there is another option that is nativescript that allow you to create your app in JavaScript and “transpire” everything into native code. Let’s say that is hybrid on asteroids. The tradeoff is that your regular web project needs to be “adapted”

One of the difficulties in building native apps is to make sure that your apps behave the same way in multiple platforms. Cross-platform frameworks help mitigate this issue, but with their own trade-offs. Regardless, it's always good to understand how native apps work in each platforms before deciding to use one of the cross-platform frameworks.

Test the app on different platforms, device sizes, and platforms to ensure that is working perfectly. Use iPhone SE for small IOS, Iphone 15 Pro Max, and Iphone 14. For Android an old phone with a small screen and the latest one to ensure everything. There are different platforms that have all the devices, on which you can run your app on ( browserstack is an example)

Automation surely can help small to enterprise company in terms of Multiplatform testing, but its also need a resources and an effort to develop such as fine test scenarios to cover up every part of the app happy path itself. Also for small companies often the features get updated / changed while the company doing business pivoting, and this can introduce to more effort of the automation and test writings. To mitigate all of it, its to make sure that features with slow changes get prioritize over the automation.

Make sure you use the right emulator and other important application packages are installed for testing. Research more on similar mobile applications.

An example I've seen of effective testing strategies involves using a combination of both manual and automated testing approaches. Manual testing allows for human intuition and exploratory testing, which can uncover unexpected issues. On the other hand, automated testing tools like Appium or Espresso can help streamline repetitive tasks and perform consistent tests across various devices and configurations. By striking a balance between these two testing methods, you can ensure a higher level of confidence in your app's quality and functionality.

Very agree with standard principles, often companies around the world waste their time to reinvent design systems, principles, ui components, and the ux flow. Meanwhile big company like Google and Apple are providing easy to use yet free principles that can cover up to their use cases, also don’t forget the big companies spent a lot of time and effort to develop such as thing. And thats can make us more easier to develop an Multiplatform app, its also open to modification which we can apply by following the principles design

One approach I've found helpful when it comes to updating and bug fixing is to prioritize user feedback. Actively encourage users to provide feedback within the app, and make it easy for them to report bugs or suggest improvements. By listening to your users, you can gain insights into the issues that matter most to them and address those concerns promptly in your updates. This not only improves user satisfaction but also demonstrates that you value their input.

Tools for bug / crash tracking can help, and its surely help when we no longer have an direct access to the released app. And tools like firebase crashlytic, sentry can help us to overwatch the bug / anr / crash, so our customers / app users can have better experiences

Bug fixing must not be customer driven. This means that customer must be comfortable when reporting glitches and collecting the relevant information you need to analyze and fix but he must not be leading this process. He naturally will tend to prioritize his case even the less relevant one. A detailed technical update and explanation is all what he needs to feel being considered and appreciated.

It’s crucial to implement ways of keeping track of bugs and to follow Crashlytics for your app, as it is a way of knowing if there’s any problem that can make the app not usable or entirely break the user experience

I think this isn’t about Multiplatform but its about developing mobile app overall, often engineers gets to creative and they just put all of the best thought into the code. And thats sometimes can make a lot of problem, the idea is to rule out the development standard and process but not to strict so we can have small creativity alongside the effectiveness. Also the style that we need to develop app from scratch needed to be humble beginnings, but we can add more later. It’s surely can help engineers when they are working in a big teams for a long terms

Tidal is a good example of multiplatform app having electron for desktop windows and Mac and mobile for iOS and android. Plug-ins are used to manage audio devices having direct access to them without issue

A true multi platform app must store its complexity somewhere else, preferably on cloud, and not in the app itself. Code complexity in the app leads to a divergent vector of both development that will end in 2 or more segregated projects and this is not the right way.

Something good to consider but it’s not mandatory is to have and test Accessibility. Your app may not be usable for people with disabilities, which, if implemented correctly, can make your app popular and/or make a good User Experience