I built a web app (formerly at the domain mapping.codes) that allows users to map multiple ZIP code boundaries on a single map with customizable styles, and export that map in a simple, easy, and quick fashion. In my own ZIP code mapping exploits, I'd found that there wasn't a great tool that does this (most are slow, ugly, or non-functional).
I don't have a background in web development (or any of the other skills required to make this project a reality), and I figured this would be a good way to get started with some of those skills. Little did I know, the steps involved were more considerable than I'd expected (contact me if you'd like to learn more).
Some things I learned in the process:
Apparently, I was the only one trying to map ZIP code boundaries on the internet? Based on traffic to this app, there are clearly very few people who have this need.
Whenever I mapped ZIP codes online, I was working with large batches and would get frustrated with the time it would take to generate these maps. I built this tool to be fairly robust and able to handle large sets of ZIPs quickly and efficiently, but I found that out of the few people who were using this tool, a majority were mapping a single ZIP code.
Things I want to build out, but am reluctant to because of limited demand for the service, generally speaking:
Search for preset groupings of ZIP codes (cities, states, congressional districts, etc.)
Support for point ZIPs (that don't have polygon boundaries)
Ability to enable labels for ZIPs
Opacity settings based on data submitted per ZIP (effectively, relative shading on a large scale)