The project centres on a straightforward, shared daily-weight form that several people can open and edit at the same time. Every entry, update, or deletion must be recorded automatically, tying the action to the user’s email-based login and the exact time it occurred, so that a clear change history is always available. I am flexible on the platform—Excel Online, or a lightweight custom web app (mobile focused) are all fine—as long as they support real-time collaboration. What matters most is: • Email authentication: each participant signs in with a verified address before interacting with the sheet/form. • Transparent audit trail: for every cell or field change, store the user’s name (derived from the email) alongside a timestamp. The log needs to be easily viewable and exportable. • Simple, clean interface: one column per user’s daily weight, or a single column with an additional “Name/ID” field—whichever you prefer—so teammates can add their figures quickly on mobile or desktop. • Edit recovery: accidental overwrites should be reversible from the recorded history. • Minimal maintenance: once delivered, I should be able to add or remove users and archive old data without touching code. Deliverables 1. Live, shareable form/sheet with concurrent-editing enabled 2. Working email login flow (no social logins) 3. Backend or built-in revision log storing username + timestamp for every change 4. Brief setup notes and a one-page user guide Feel free to use familiar stacks—Google Apps Script, Microsoft Power Automate, Firebase, or a small Node/React bundle—so long as the final product meets the points above and stays easy for a non-technical owner to manage.