Who owes whom after a trip? I built a free split-expense app with no sign-up

With eight friends it is hard to keep track of who paid for what. Dinner, taxi, tickets, groceries: one person pays, the others say “I’ll send it later”, and by the end nobody remembers. We tried a chat and a spreadsheet, and both fell apart in a day. The apps for this exist, and I installed a few, but my friends either refused to sign up or the app wanted money for currencies. So I built my own.

Download: iOS · Android

What it is

The app is called kisir. It has one job: open it and see who owes whom.

1. Create a group.
2. Send a link to the chat or show a QR code.
3. Everyone types a name, and that’s it, they’re in. No email, no password, no account.
4. Everyone adds expenses, and the app does the math.

What it does

No sign-up at all. Just a name. If a friend can’t or won’t install the app, add them to the group as a member without a phone: you type their name, and the app counts their share with everyone else’s.

Every expense has its own currency. Dinner in drams, tickets in euros, someone paid back in roubles: fine. The day’s rate is filled in automatically, and if your bank charged a different one, you can correct it by hand.

The fewest transfers. Five people are not ten “everyone pays everyone” payments but at most four. The app gives you the list: who pays whom, how much.

Works offline. Log an expense in the mountains or on a plane; it waits for a connection and syncs itself.

Free, no ads, no paid features.

How I built it

This is probably the interesting part: I didn’t write a single line of code by hand. The server, the database, the screens: Claude Code wrote all of it from my descriptions. I said what should be on the screen, it built it, I checked on my phone and said what was wrong.

The first working version, with groups, expenses, settlement and joining by link, took about five hours. Then came two more months: currencies, offline mode, the app stores, Russian and Armenian. So “five hours” is the first version, not the finished product. But without those five hours I probably wouldn’t have started.

What it doesn’t do

It doesn’t scan receipts, doesn’t connect to your bank, and there is no web version. iPhone and Android only. If you need any of those, one of the bigger apps will suit you better; our comparison of expense-splitting apps is honest about that.

How do you split trip expenses: a chat, a spreadsheet, an app? Write to support@kisir.am and tell me what annoys you about it. I built this for myself and my friends, and I want to know what’s still wrong.

This story was first published on Medium; the Russian version is on vc.ru.