Flutter(Dart) vs Javascript - which is better for developing cross platform & web apps ?

Job ID: 38013244

Budget: ₹600 – ₹1,500 INR

I need an expert to help me select the most suitable all in 1 programming language for building various applications targeting multiple platforms (mainly web)

1. I would like to build applications for Web, iOS, Android, Windows 10, Linux, and MacOS & embedded systems (like micro controllers) from single code base
2. I want to learn a language in which we write a code once and can compile for any platform.
3. One possible answer to my questions is JavaScript. We can build server side apps in JS using Node.js & Next.js. Javascript can be embedded in HTML on client side too. We can build desktop apps in JS using Electron and we can make mobile apps in JS using react & angular. But in javascript will code be exactly same for all platforms ?
4. Another option is Flutter (Dart).
5. Which is better out of these 2 ? or can you suggest any other option apart of these 2
6. As of now I want to develop a web app for visual DBMS quite similar to ms access. It will look like a spreadsheet but will have capabilities of both Google sheets / MS excel & a DBMS (DataBase Management System)
7. I am very familiar with C & C++. So I would prefer to use similar syntax.
8. Can C++ be answer to my 1 & 2 point ?

You should have:

- Profound understanding of various programming languages
- Significant experience in building applications across platforms
Related categories: JavaScript Dart Node.js Flutter Next.js