Project: a lightweight budget app for my android device. I couldn't find anything that didn't want to sync with my bank account, and I'm sure not going to do that. Ideally, I open the app, it opens quickly, I punch in a $#, and close it.
So far this is going pretty well and while it isn't ready for public consumption I've been dogfooding dev versions for a month and successfully built a habit of using it, so it will work, at least for me!
Three problems: 1. I am not an android developer (yet)
2. there are difficult questions surrounding how to change a budget in the middle of a running period, for example two weeks into a month, altering the budget from $400/mo to $50/wk -- Those intervening two weeks must be handled neatly. What about dealing with time zones? A user could set up a budget to turn over on the first of every month, enter a neighboring timezone and spend money on the 31st while it's already the 1st in their primary time zone. This is tough, and how that is handled matters a lot to questions about what happens if a user permanently changes their time zone after setting up a budget. This is a fun data structures & UX problem.
3. Getting home from a long day of programming at work and wanting to continue programming is not easy.
Another project:
Expression pedal router. Effects pedals that accept expression input are nice, and if you have more than one and want to control more than one with a single expression pedal in a live setting, you will be doing a lot of crawling, plugging & unplugging in the middle of a set. Even in a non-live setting this is a pain, especially if the pedalboard is crowded. The solution is a routing box that all the pedals can be plugged into as well as the expression pedal, and rout the signal from the expression pedal to an effects pedal selected by a rotary switch.
Unfortunately it is not that simple, because having the expression jack filled will alter the sound of the non-selected pedals, and with that circuit open will have whatever setting is controlled by the expression pedal fully dry or wet. The real solution is a much more crowded active circuit that drives a network of SSRs to either pass any given effects pedal through to the expression pedal or to a local potentiometer to replace whatever knob on the pedal is being overridden by the expression input.
That's a lot more expensive and can't be effectively hand-wired in a reasonably sized enclosure, so the problem I face is taking the dive and ordering the prototype boards, but I'm afraid to waste the money if it turns out I actually don't know what I'm doing laying out circuits with CAD systems. Instead of having my nice expression pedal router I've been sitting on this project for a few months for fear of throwing away $120 on (mostly) components & PCBs.