Where to save preferred language in React app? 

When developing a React app, it's essential to save the user's preferred language to avoid requiring them to set it each time they access the app. This information can be stored on either the client or server side.

While it may be convenient to store the preferred language on the client side, this approach is limited as it won't work if the user opens the app on a different browser or device. Therefore, if you want to ensure consistency across all platforms, it's better to save the preferred language on the server side.

The most effective way to do this is to store the data in a database on the server, but this may require additional coding. By doing so, you can ensure that the user's language preference is always saved and accessible whenever they use the app, no matter which device or browser they use.