Choosing a cross-platform framework, allows you to build apps for any kind of platform; such as web, desktop and mobile.
All of this without having to learn different technologies in the process. You can learn one programming language, and build many kind of applications. Such a great thing, right?
The ability to build applications for many kind of platforms reduces costs and also time. Years ago, if you wanted to build an Android app, you probably would have chosen Java. Or if you were planning to release the app on iOS, then Swift would have been a reasonable technology to work with.
As you can imagine, learning this two technologies were not impossible, but a time-consuming and very improbable thing. What developers were used to do (and still do) was specializing in one, such as Android or iOS option.
And my post goes in this way. We've seen a very interesting Flutter's growth across time. As you can see in the next Stackoverflow trends' graphic:
This other Google Trends graphic, shows the next:
As we can see, trendings indicate Flutter is growing at least in interest of the dev community. Big firms like Tencent, Alibaba Group, Ebay and many others are starting to adopt this technology as its base language to start to build new cross-platforms apps.
In the FOSS community, Canonical has just announced they will adopt Flutter as its main technology for mobile and desktop developments.
So... these are not fixed trendings, of course. They may vary over time.
I read you in the comments!