Hey PH!
My girlfriend and I constantly had the exact same conversation: "Wait, who paid for groceries yesterday?" or "Did I send you my half for the dinner?"
I got tired of it and built a solution. I'm a solo Java dev, so I built a native Telegram Mini App called Kopilo (launching soon!).
The feature I spent the most time on is "Shared Spaces." You add a partner or a roommate directly via a Telegram invite, set permissions, and all joint transactions and debts are calculated automatically in real-time via WebSockets. No more awkward math, no more separate apps to download.
Hi PH. I'm Alex, a solo Java dev from Belarus.
Kopilo started because I was tired of opening finance apps that asked me to create an account before I could see anything. I use Telegram for hours every day. My partner does too. Everyone I know does. So I thought: why not just build the tracker there, where people already are?
That was naive. Telegram Mini Apps have their own quirks. The WebKit black screen bug on iOS ate two days. Getting Telegram Stars payments to work required me to anonymously override a validate() method in a Java library because the library refuses to accept an empty provider token, even though that's exactly what Telegram's own API spec requires for Stars. There's a comment in my codebase about it that I will never delete.
The stack: Java 21 + Spring Boot 3 + PostgreSQL + Redis on the backend, living on a OVHCloud VPS. React 19 + TypeScript + Vite on the frontend, on Vercel. For AI I'm using Gemini's native SSE API directly, no wrappers, because every abstraction library I tried added some parameter that broke the stream.
I called the design language "Liquid Glass Finance." 3D account cards, glassmorphism panels, HSL rainbow progress bars on budgets that go from green to red as you spend. Finance apps are almost always grey and boring. I don't think they have to be.
Nine phases from blank repo to this. Right now I'm at phase 9 - domain, scaling, getting real people to use it.
The feature I'm most curious about in terms of user reaction: shared Spaces. You add a partner or roommate, set permissions (can they add transactions? see analytics? manage budgets?), and debts between members are tracked automatically. Real-time via WebSocket. I built it because my girlfriend and I kept having the "wait who paid for groceries" conversation. We don't anymore.
7-day free trial, no card needed. Just Telegram.
Would love to know what finance tracking problem actually bothers you. I have a feedback form built into the app and I read every submission.