What a bill-splitting app needs to know about you: a name

The minimum

Start from the problem. A group of friends has shared expenses, and at the end they want to know who owes whom. To answer that, you need:

• the people in the group, by whatever they want to be called,
• each expense: how much, who paid, who it was for, how it’s split,
• the payments people made to each other along the way.

That’s it. Nothing about the problem needs an email, a phone number, a bank account, a location, a spending history across groups, or a profile of your habits. Everything an app asks for beyond the list above is for the app, not for the arithmetic.

kisir asks for the list above and nothing else. This post is the inventory.

What kisir keeps

Your display name. Whatever you type on first launch. It can be different in each group. It’s a label that says who paid, not an identity that proves who you are.

Your groups. Who’s in them, every expense with its history of edits (who changed what, old number to new), every recorded payment, and each group’s currency.

An optional recovery email. You can add one in Settings or never. It does one job: it restores your groups when you set up a new phone. It isn’t a login, it doesn’t unlock anything, and the app works identically without it. There’s a longer post on why kisir has no sign-up.

A note on the feedback form, if you send one, with your email if you choose to include it, so a person can reply.

That’s the whole inventory. It fits in a paragraph because there isn’t more.

What kisir doesn’t keep, and why each one is a choice

No account. No email required, no password, no verification. A friend in the chat taps the link, types a name, and is in the group in ten seconds. Every field we could have added there would have cost us the casual members, the ones who came to one dinner and are exactly the ones who owe or are owed something.

No bank connection. kisir doesn’t move money, send payment requests or read your transactions. You pay your friend the way you always did, then tap to record it. Connecting to a bank would mean holding the kind of credentials a small app about dinners has no business holding.

No receipt images. Receipt scanning would mean photographs of bills, with the restaurant, the date and the card’s last digits, going to a server. We don’t scan receipts, and the reasoning is in why kisir does not scan receipts.

No profile, no habits, no learning. This is the one that comes up most in 2026. A “smart” expense app needs to learn from you: what you usually order, how you usually split, when you’re likely to pay. kisir has no model, so there’s nothing to train and nothing trained on your groups. The app on day 300 knows exactly what it knew on day one, which is the expenses you entered.

No ads, so no ad tracking. Most advertising works by knowing something about the person looking. A screen that shows what your friends spent and who owes whom is a bad place to start collecting that. kisir has no ads, and the post on free, no ads, no limits explains the rest of what that covers.

No location, no contacts, no calendar. The app doesn’t ask for them, because the arithmetic doesn’t need them.

What the group can see, and what it can’t change

Inside a group, everyone sees everything: every expense, every balance, every payment. That’s deliberate. A ledger three people can see and one person can’t isn’t shared.

But seeing isn’t changing. Only the person who added an expense can edit or delete it, and every expense keeps a history of who changed what and from which number to which. Nobody can quietly adjust a figure someone else entered. That rule does the job that accounts and permissions do in bigger systems, without asking anyone to make an account.

One honest caveat: the group’s link is the way in, so anyone who has it can join. A name in kisir is attribution, not security. For a trip, a flat or a dinner among people who already trust each other, that’s the right level. Share the link where you’d share the plans.

Your data goes with you

The part of this I care about most is the exit. The whole ledger exports to CSV or Excel, free, any time. If the numbers are yours, you should be able to take them out and keep them in a spreadsheet, send them to the one friend who wants one, or just have them. The export guide shows how.

An app that knew more about you would have more to keep, more to protect, and more reasons to make leaving hard. An app that knows your name and your groups has none of those reasons.

The short version

A bill-splitting app needs the names and the expenses. kisir keeps those, plus an optional email for getting your groups back. It has no account, no bank link, no receipt photos, no profile, no ads, and no model learning from any of it, because none of that is needed to tell Dan he owes Ana €40.00.

If you’re comparing apps on exactly this, the no-sign-up guide explains how joining works without an account, and the no-account Splitwise alternative guide sets it next to the usual choice.