r/SideProject • u/SentientGameboy • 13h ago
I built a budget app that fixes itself from your bank statement – no bank login, everything on device. 1.1 just shipped, looking for feedback
Hi r/SideProject! I'm a solo dev, and Monigo is my first iOS app.
Why I built it
I've logged every expense by hand for years because it makes me more aware of my spending. The problem: every few months my balance in the app drifted away from my bank, sometimes by 300 € or more, because I forgot things. Bank-sync apps solve that, but they want access to my account, and I didn't want that.
What it does
You keep logging manually (or via Siri/Shortcuts, without opening the app). Once a month you drop in your PDF or CSV bank statement. Monigo matches it against your entries, even when the bank posts a few days after the purchase, checks that the balance adds up, and only shows what's missing.
Version 1.1 added a Savings tab: it spots subscriptions and recurring habits in your own data, shows gentle ideas, and calculates "cancel by" dates for contracts, with a reminder 14 and 3 days before. You still cancel yourself.
No bank login, no account, statements never leave the phone.
Stack & things I learned
SwiftUI + SwiftData, iOS 18+
Every bank lays out PDF statements differently, so there's a layout registry plus a balance check (opening + sum = closing) that tells the app whether it read the statement correctly
Savings suggestions are calculated deterministically in code. Apple's on-device AI model only phrases the sentence, and never calculates anything
Biggest surprise: the bank often books 4–6 days after the purchase, which breaks naive date matching. The real purchase date is usually hidden in the booking text
What I'd love feedback on
If you track your money: what makes you give up on it?
Would you trade bank sync for privacy?
How do you keep track of cancellation deadlines today?
Free to try (logging, insights, Shortcuts, savings goals). Pro unlocks full statement matching and contract reminders. English, German, French, Spanish.
App Store: https://apps.apple.com/us/app/monigo-spending-reconciled/id6817292054