In 2018 I was $30,000 in credit card debt. A friend told me about a practice from a 12-step program for people with spending problems: keeping your numbers. It just means recording everything you spend. I started logging every transaction, every day, in an app called AndroMoney. Within two years I was out of debt.
I kept going. After eight years I had a huge amount of data. But getting real insight out of it always meant exporting the data to a spreadsheet and manipulating it there. That worked when I had the enthusiasm for it. When my enthusiasm waned, I fell off. The logging continued but the understanding stopped.
AndroMoney was functional but clunky. I tried other apps, but they required me to connect my bank account before I could even access the product. That was an immediate no. The whole point of this practice — for me — is the conscious act of recording. Handing that to a bank sync defeats the purpose entirely.
The moment I decided to build it
I started building software tools with Claude Code for my own business in early 2026, and somewhere in that process I realized: I could build this myself. Not just a logging app, but one that gave me the visibility and analysis I'd always had to construct by hand in spreadsheets. The kind of app I'd actually wanted for eight years.
I also realized something about the habit itself. Manual tracking had permanently changed the way I think about money. Not because of the data — because of the pause. Every time I logged a transaction, I spent a few seconds being conscious of what I did. That's it. That's the whole mechanism. It sounds almost too small to matter. It isn't.
The goal isn't to overwhelm you with your finances. It's to give you a few seconds of awareness, thirty times a month.
Most finance apps either do too much or log passively in the background. Neither built the habit for me. When a bank sync did the work, I stopped noticing what I spent. Carlo is built on the opposite premise: you keep the record, and Carlo makes keeping it quick.
What Carlo is — and isn't
Carlo is not a comprehensive financial planning tool. There's no retirement calculator, no net worth tracker, no debt payoff scheduler. If you want those things, other apps do them well. Carlo does one thing: it builds the habit of knowing where you are before you spend, every day. If you check in once or twice a month, you're flying blind the rest of the time. Carlo is designed to make the quick daily check-in so easy that you actually do it.
Carlo never requires a bank connection, and it never will. You log what you spend, and Carlo shows you what that means in real time — not just totals, but how much you have left per day for the rest of the month. For me, that number does what a monthly summary never did: it's there while I'm deciding. If you want a safety net, Bank Reminders can optionally surface purchases you forgot to record — but the logging, and the noticing, stay yours.
Built on real feedback
I use Carlo every day. It's the only financial tracking tool I use. I've shown it to my friends and anyone who'll listen, and I'm constantly incorporating what I hear — making it faster, simpler, easier to pick up and stick with.
Carlo is built by one person. That means it moves fast, stays lean, and never has to justify a bad decision to a committee. It also means I read every email. If something isn't working for you, tell me: [email protected].
Alex Marcus
New York, NY