Since its introduction in 2013, React Native(RN) has earned the title of one of the most widespread frameworks for multi-platform app development. Support from industry giants and an extensive community make RN the first choice among JavaScript development environments.

That is why many entrepreneurs use React Native services in order to bring their app ideas to life. Often, service companies work out their own development mechanisms, trying to satisfy customer requests. However, any RN developer knows that there is always room for improvement. If you are looking for the best ways to optimize your application, you’re in the right place.

Here are 6 tips to make your React Native app rock-starish.

Database query optimization

Database queries may be tricky. The main idea that helps to optimize this issue is this rule – many simpler queries are better than one complex one. This is due to the fact that in a complex query with a large selection it is difficult to use indexed database columns as efficiently as possible. Performing a simpler query, the database will select only indexed columns, which makes the whole process much faster.

Complicated query conditions can cause the database to stop using indexed columns and start fetching across all records. This is due to the specifics of working with indexes, which means that with a large combination of columns, a situation may arise when indexes will no longer be taken into account. At the same time, using simple queries does not cause such a problem.

Image optimization

Images take up a lot of free space in the app. That’s why reducing their size can help too. Use the aspectRatio and resizeMode commands.

Another problem associated with images is caching. Many cached images slow down the application. It is a good idea to disable caching and focus on ensuring that your images always load without delay and don’t make the user wait. In general, the maximum reduction in cache requests is a nice practice that should be applied constantly and not only to images. Of course, depending on the kind of application, it may demand a different amount of information updates and, accordingly, requests for elements’ caching. Therefore, you need to carefully study your application and, if it does not require regular changes in the data value, make the cache frequency rarer.

Another good tip: use the PNG image format, since it is the most suitable one.

Update on time

Update on time

The RN community is very large, so the framework undergoes constant improvements. Skipping a fresh update is a common mistake.

Updates are extremely useful, as they can carry new features that will optimize your application. A few examples include a new Hermes engine from Facebook and a more accelerated method of page reload — Fast Refresh. By installing such updates, you instantly optimize your application without additional effort.

Watch for FPS

In order for the dynamic FPS value to appear on your screen, you need to open the dev tools and turn on the Performance Monitor feature. Most often, FPS will sag on the JS side of the elements. Conduct a study and try to figure out which places the FPS draws the most and optimize (or delete) these areas.

In fact, this is a very important point. If the JS element was unavailable for some time, then its status changes to Dropped. The frame rate of your JavaScript code matters, because this is what affects all the processes and all the logic. All requests come here after each iteration and should also be sent back in time.

Improve UI

The process of optimizing the app’s UI causes many problems. Perhaps, this is due to the features of the framework itself. Still, improving the app’s UI is always a good idea.

To optimize UI, make sure that the rendering of all your elements passes through the Pure Component feature. It modifies the shouldComponentUpdate lifecycle method, mechanically checking whether the component needs to be redrawn. At the same time, PureComponent will trigger the render only if it detects shifts in a condition or props of the element. It means that you can change the state in all components without coding.

Optimize navigation

Navigation between the JavaScript code and Native elements has been a problem since the very first days of React Native. Application performance suffered due to delays in communication between the two structures. On the JavaScript side, a component called Navigator is responsible for navigation. Many developers believe that its performance indicators are relatively weak. For example, this component does not work well when it is necessary to provide smooth navigation between the elements of iOS and Android systems. When adding new features to the native code, the application begins to lag on the side of JavaScript.

In order to solve the problem of navigation between iOS & Android elements and, therefore, optimize a multi-platform application, you can use the React Navigation. This application allows you to create custom navigation between different elements from scratch, or use ready-made APIs.

There are more specific solutions like Navigatorator. However, this application was created exclusively for iOS and, therefore, problems arise when there’s a need to synchronize navigation with the Android system.

In conclusion

Although React Native remains the main framework for developing multi-platform applications, it isn’t an ideal solution. Problems exist, and optimization options prove this. As the last tip, we want to say that the best practice in the process of optimizing React Native applications is picking the skilled development team. The more experienced the programmers are, the more likely you will get a well-optimized app within a short period of time.