OBD2-powered used car inspection app for non-mechanics

The core insight: every used car buyer should get a pre-purchase inspection, but most people skip it because it costs $150-300 and requires scheduling with a shop. Meanwhile, a $15 Bluetooth OBD2 dongle can read engine codes, sensor data, and system health - but the raw data is incomprehensible to anyone who isn't a mechanic.

Build a mobile app that connects to any ELM327 OBD2 adapter via Bluetooth. Run a full diagnostic scan. Then translate the results into plain English: "Engine: healthy, no fault codes. Transmission: 2 minor sensor warnings - not urgent but negotiate $200 off. Battery: weak, likely needs replacement within 6 months ($150-200)." Add a used car buying checklist with photo documentation - rust spots, tire tread depth, fluid colors.

The app becomes the buyer's advocate. Before you hand over $15,000 for a used Camry, spend 10 minutes scanning it. The report either gives you confidence or saves you from a lemon.

Freemium model: free basic scan (check engine light yes/no). $4.99/scan for full diagnostic report with plain-English interpretation. $29.99/year unlimited scans for dealers and frequent buyers. Bundle with a branded OBD2 dongle for $39.99 (dongle + 5 scans included).

At 100,000 paid scans/year at $5 average, that's $500K. Add 10,000 annual subscribers at $30, that's another $300K. The 72K-upvote post proves the demand exists at massive scale. The OP validating by building it himself is the strongest signal possible.