Software for One: How AI Makes Personal Apps a Reality

Things I've built in the last month or so:

* A personal music player for Apple Music with an embedded agent loop, so I can say things like "I'm going to work in the wood shop, play woodworking-appropriate music and keep the playlist full and non-repeating indefinitely".

* A calorie/protein tracker that takes 1-liner summaries of meals, resolves them to macros with GPT5 calls, and tracks them in SQLite.

* A macOS menubar combined Apple TV and Roku TV remote control.

* A calculator front-end to SageMath that renders Latex math notation and has point/click shortcut affordances for linear algebra and MVC.

* A "self driving wiki" macOS desktop llmwiki that imports and digests PDFs.

* A menubar tracker for the little temperature sensors I have scattered all throughout the house so I can click my menubar and instantly see the temps in the different rooms of the house.

* A layout tool for designing picture frames to get cut lists and rabbet depths and stuff.

That's just the desktop stuff. These applications are generally better than what I'd get from the App Store. The calorie tracker is one of the better-designed apps on my dock.

I feel like I'm not doing this enough yet, it hasn't fully sunk in, and I'm going to be building a lot more stuff when it does sink in. I haven't yet gotten to the point of writing my own note-taking application (still Bear.app for that), but how long can that last?

I've got a few of these.

There's one in particular that I use quite often and have for about a year, vibed for myself: it's a chat interface that walks you through processing an emotional or difficult moment, following a process / workflow. Supports Martin Seligman's ABCDE and Byron Katie's "The Work". Two techniques that I found most useful to improve my thinking and responses to difficult situations. You converse with it, and it leads you through the stages of the selected flow. More than a system prompt - it tracks and progresses through the workflow at the right times, and you download a consistent pdf of key details from the "session" at the end for your records.

The thing is, I can't sell it. I don't even think I can open source it. It's mental health (minefield of legal and ethical issues), and would probably breach copyright, trademark etc law.

Yet it's very useful to me. I guess it's the equivalent of making a system to do these things at home, like prompt cards or key points taken from the books, with a well formatted note taking structure. Except it's way easier because you just chat like you're talking to someone.

I would never have spent time building this. But now it's so cheap and easy to do.

Since the advent of these coding assistants, I gathered a list of software tool ideas I usually discarded due to lack of time. No more! Main one on that list: grocery assistant, with a barcode scanner for empty packaging to order new stuff, inventory management, coupling to recipes and most importantly: automatic ordering for delivery.

There's existing stuff for this but making a personal extension to this should be very well possible too.

> sleep consultant

I'm not sure I believe this is a real job. Do we really need to pay consultants to tell us that babies need naps?

Side note, why not just deploy onto a VPS and save the money from using hosted services, as well as protecting yourself from when they inevitably go down? The CBA clearly shows that while active development is going on its trivial to have hosted service subscriptions because the AI sub is way more, but what if that sub disappears? You're left paying (relatively) exorbitant amounts compared to $1-10 per month per VPS for life, or less if you have the privilege and wherewithal to self host. It's also dead easy with AI. Maybe this just reinforces how much a personal runtime solution is needed, as stated in YC's recent RFS.

This was really interesting, but I admit I bumped on this throwaway detail:

> Our sleep consultant's plan arrived as a PDF full of conditional logic: wake windows, nap caps, what to do when a nap fails

Every so often, you get a glimpse into a whole world you never knew existed.

This mitigates problems with LLMs' low quality code. For a single user, the bar is much lower. The app doesn't have to have all the features that work for everyone's edge cases, implemented in a way that other devs can maintain. It only needs to be good enough for one user, and can be discarded and recreated when it gets too messy.