Turning WhatsApp Into a Mobile ERP for Field Logistics (Apps Script + Google Sheets)

Field-service software has an adoption problem: drivers won't use it. Heavy app, another login, crashes in low-signal areas. So the "real-time" data still shows up as end-of-shift phone calls. The fix that actually sticks: stop building an app and use the one drivers already live in — WhatsApp. With Apps Script and Google Sheets behind it, WhatsApp becomes a frictionless mobile ERP. Here's the build. WhatsApp as a data-entry terminal A driver texts Status ABC-1234 Delivered . An Apps Script doPost webhook receives it, parses it, and updates the Sheet in real time. Latency goes from hours to milliseconds — and there's nothing to install, so adoption hits 90%+ in a week (vs. 50–70% for custom apps). Two-stage parsing for messy input Real drivers type "done," not clean commands. So: Regex first pass — handles ~70% of messages (clean format) instantly and for free. LLM fallback — the remaining ~30% goes to a cheap model (GPT-4o-mini / Gemini Flash) with the known cargo IDs and valid statuses. It returns normalized JSON + a confidence score. Below-threshold messages surface to a dispatcher. The LLM normalizes correctly 95%+ of the time (~5% manual), and it handles multilingual input with zero extra code. Driver msg → Apps Script doPost → regex pass → (fail) LLM fallback w/ confidence score → Sheet update (timestamp + raw-message log) → optional outbound (route change, POD photo request) Why Google Sheets is the right backend Dependent formulas: time-to-delivery, SLA-breach flags Pivot tables for reporting Apps Script triggers for automatic client emails Conditional formatting dashboards Native Calendar / Maps / Drive integration (POD photos → Drive folder) It runs on free Google Workspace infrastructure with minimal API cost. Bidirectional by default The same integration pushes messages back to drivers: route changes, delivery instructions, shift reminders, exception alerts, proof-of-delivery photo requests — all in the same thread. Pitfalls that get your number banned T