I built an AI app that scans marketplace listings and tells you if you're getting ripped off — honest results after 5 months

Full disclosure — I'm the developer, so take this with a grain of salt. But I think this community would appreciate an honest breakdown of what the AI actually does well and where it falls short.

The app: Snag AI (iOS). You point your camera at any marketplace listing — Facebook Marketplace, OfferUp, Poshmark, Craigslist, Depop — and the AI analyzes it in seconds.

What the AI does:

- Price analysis: Compares the listing price against market data and tells you if it's fair, overpriced, or a steal

- Red flag detection: Spots signs of scams, hidden damage, or misleading descriptions

- Negotiation scripts: Generates a copy/paste message you can send the seller to negotiate a better price

Under the hood: It uses the Claude API (Anthropic). You screenshot a listing, the app sends the image to Claude with a structured prompt, and it returns pricing analysis + negotiation strategy. The whole thing runs through Supabase Edge Functions.

What actually works well:

- The AI is surprisingly good at identifying overpriced listings. It catches things like "this 2015 Honda Civic with 150K miles is listed at $3K over market value" consistently

- Red flag detection is solid — it picks up on vague descriptions, missing photos, and pricing that's too good to be true

- The negotiation scripts are genuinely useful. They're specific to the listing, not generic templates

Where it falls short (being honest):

- Niche or rare items are hard. If it's a limited edition collectible, the AI doesn't always have good pricing data

- It can't verify physical condition beyond what's visible in the listing photos

- Sometimes the negotiation scripts are too polite. Real marketplace negotiation is blunter than the AI defaults to

- The free tier (3 scans/week) is limiting, but I had to cut it from 3/day because nobody was upgrading

v1.3.0 just dropped with a new onboarding flow that gives you a 7-day free trial of Pro (unlimited scans). Also running a $100 giveaway — whoever saves the most money using Snag in a month wins.

Would love to hear from anyone who tries it. I want real feedback, especially on where the AI analysis could improve.

App Store: https://apps.apple.com/us/app/snag-ai/id6758535505

Waitlist for updates: https://www.snagai.app/waitlist