NOW ON THE APP STORE

Say what you spent.
That's it.

Mäuse is the expense tracker for you and your favorite Maus. Log it, slice the cheese, and always know who owes what - right on your iPhone.

"Paid forty-two fifty for dinner at Luigi's" - logged.

Download on the App Store View the source

"Mäuse" is German slang for money - literally "mice".

Mäuse

JULY 2026

€213.50 Your Maus owes you €107.30

GO AHEAD, IT'S THE REAL APP - TAP AROUND

Everything a Maus needs.

Nothing that nibbles at your attention.

Fast as a mouse

Amount, note, done. Logging an expense takes seconds, not taps.

Slice the cheese

Split by percent or a fixed amount, with preset chips for the usual 50 / 30 / 70 / 100.

Squeak to log

Say what you spent - even a few things at once. Mäuse drafts them, you tap save.

€

The monthly stash

Totals per month and exactly what your Maus owes you. No spreadsheets, no math.

Listening

Save 2

Squeak away - "add flowers for 12 euros…"

Add flowers for 12 euros and two cinema tickets for 24 - split both in half.

Got both! Two expenses in the trap - check them below.

IN THE TRAP · 2 €36.00 total

Flowers

€12.00

50%Today

Cinema tickets

€24.00

50%Today

Talk. It's logged.

Tap the mic It's right there on the main screen.

Squeak away "Flowers for 12, cinema tickets for 24 - split both in half."

Check the trap Review the drafts it caught, then save them all at once.

Voice mode is optional. Your API key is stored in Keychain and sent only to OpenAI over HTTPS; live audio and expense details are shared with OpenAI only during a voice session.

Local first. Clear about cloud.

Manual expenses stay on your iPhone. Voice Mode connects directly to OpenAI only after you choose to enable it.

Manual expenses stay on your device. Amounts, notes, dates, splits, and imported backups are stored locally on your iPhone.

Works offline. On a plane, in the basement, in a mouse hole - logging always works.

No app account, ads, or tracking. The iPhone app has no analytics or telemetry. This website uses cookie-free, aggregated Vercel Web Analytics.

Portable backups. Export your data as a file, import it anywhere. You own it.

One optional cloud connection. With your consent, Voice Mode sends live audio and spoken expense details to OpenAI. Your key is stored in Keychain and excluded from backups.

See every crumb.

The Mäuse source is publicly viewable on GitHub for transparency. Read how local storage, backups, and Voice Mode work.

Browse the code

Say what you spent.That's it.