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SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
If you want to explore deeper, there's some fun (and well commented) open source GPS processing codes in Octave/Matlab [1], coming from the excellent book [2]. Those are compatible with cheap RTL-SDRs. [3] also looks nice, but as I recall is Linux only.
[1] https://github.com/kristianpaul/SoftGNSS
The author wrote his own WebGL library. If you don't have much knowledge about 3D, then https://threejs.org/ is a fantastic library to learn.
Not sure what's the best starting point to learn, but there's lots of videos on YT to help you get started.