IOUPAY: IOU & Loan Tracker

IOU Pay is a peer-to-peer digital IOU and loan-tracking app that lets two people create, agree to, and keep an honest shared record of money lent between them. It turns informal "I'll pay you back" arrangements into clear, timestamped, mutually-confirmed agreements without the awkwardness of chasing someone or the guesswork of who paid what.
At its core is a dual-user model. One person sets the loan terms principal amount, interest rate, payment frequency (weekly, bi-weekly, monthly, or lump sum), and repayment duration and the other reviews and accepts them through a "digital handshake." Both parties actively sign off from their own devices, producing a verifiable acceptance record with unique user IDs, email confirmation, and cryptographic timestamps. Nothing becomes binding until both sides confirm.
Once terms are accepted, a built-in Calculation Engine automatically works out the full repayment schedule: each installment amount, due dates, interest breakdown, and running balance. Borrowers can overpay or pay early with no penalty, and the schedule recalculates in real time whenever payments or authorized changes happen.
Payment tracking is designed to stay in sync across both users, even offline when a device reconnects, records reconcile automatically so both people see the same balances. To prevent disputes, IOU Pay uses a "Truth Factor" confirmation mode: a payment is only marked settled when both users sign off on it, so neither side can misreport what was paid. An automated reminder system sends due-date alerts and missed-payment notices to keep everyone accountable.
Crucially, IOU Pay is a personal tracking tool and neutral record-keeper only. It is not a bank, lender, credit provider, or payment processor. It does not issue loans, move money, guarantee repayment, or enforce agreements all IOUs are private, informal records between individuals. Agreements are built to be E-SIGN compliant and include a usury savings clause that auto-adjusts interest to a state's legal maximum, but enforcement of any debt is strictly between the two parties.
Your data login details, profile, IOU records, and manual payment statuses is stored securely via Firebase Authentication and Firestore, never sold or shared with third parties, and deletable on request. The app isn't intended for users under 13.
In short: IOU Pay brings structure, transparency, and mutual accountability to personal lending between friends, family, and acquaintances a clear digital paper trail for money matters that usually rely on memory and trust.