"Complex" is not for laymen. There is only so much that you can do with any "appliance". Beyond that, you actually have to know what you are doing. This "problem" has nothing to do with programming.
This. Thinking about the web apps I've written, most of them required fairly deep knowledge in the area of the app -- auroras, photography, specialized group management, history, genealogy, measuring instruments, Chinese, retail procedure -- all areas an interested party could potentially bring to the table.
But the tools to instantiate, manipulate and present those ideas? Those simply don't exist in "amateur" form -- I had to create them. And in doing so, I used knowledge starting with HTML and CGI and CSS, but which extended well into Python, (replaced Perl), C, SQL, a fair bit about the underlying structure of the host OS(s), knowledge of how to structure an application in the first place, and to wrap it all together, a fairly deep knowledge of what's efficient and what isn't.
Now I will admit that I am particularly resistant to Other People's Code, partially because I am unwilling to be subject to other people's bug fix schedules (or lack thereof), and permissions (or lack thereof) and functinonal choices (or lack thereof); and partially because the more stuff I write, the more handy tools of my own I have to bring to bear on the next problem that depend on no one but myself and the host language(s) -- which frankly is quite enough dependency for me anyway. Plus it's been writing all this stuff that's made me a decent programmer in the first place. So even if there *were* a library out there to generate general purpose readout dials, I wouldn't have used it; the result would have been the same. All my own code. Not the least bit reluctant to reinvent the wheel.
Still, the idea of making all that stuff both available and trivially usable (and that's what we're talking about here, because a non-programmer will have to hit this at a trivial level) seems to me to have been tried multiple times in multiple venues, and to have failed every time. Personally, I think it's because as programmers, we underestimate the complexity because we've internalized so much; we can't see the actual level of difficulty very well, because it starts out relative to our own skills. This has resulted in quite a few attempts to "make it easy", and none of them have hit any serious stride. The best any of these can boast is a small following making very limited applications, if you really want to stretch what "application" means.
I don't think the idea is ready to fly. The only context I can visualize this actually working is where you have some *very* smart software that can take an abstract description and write code *for* you. That software would have to be (a) very damned smart and (b) conversant with an enormous range of general human knowledge. Right now, as far as I know, that's the precise description of a competent applications programmer. And nothing else.