Every action, who did it, when. Tamper-proof.
Activity page (in the sidebar) shows every action chronologically with member attribution. Useful for couples ("did you pay rent?") and tax-season audits.
Payments (with amount, method, notes), bill edits, member invites + acceptances, splits, reminders sent, attachments added. Each entry timestamped and attributed.
Audit log entries can't be edited or deleted — even by superadmins. Deleting a payment from the bill drawer creates a new audit entry ("X deleted a payment of $Y from..."). This is intentional: tax-season and couples-disputes both benefit from an unforgeable timeline.