iPhone Duo is here. Here are 9 startup ideas I’d build for it: 1. Mobile sales room: prospect profile on one side, live call notes + objection scripts on the other 2.Pocket CAD for trades: plumber/electrician sketches room measurements with Pencil, app converts to parts list, code notes, quote. Beats Autodesk. 3. Contractor estimating app: blueprint/PDF on one side, materials calculator + margin controls on the other 4. Jewelry trade in app: customer sees instant offer, buyer sees authenticity checks, comps, resale margin. 5. Two sided live translator for businesses: clerk and customer each see their own language on opposite screens. Sell to hotels, clinics, immigration lawyers, luxury retail. 6. Pocket notary / witness app: signer sees the doc, operator sees ID verification, fraud checks, and legally required prompts. Charge per notarization. 7. Field medical consent: patient sees plain-language consent, clinician sees risks, contraindications, charting, signature. 8. Tow truck accident intake: driver captures scene/photos closed, unfolds on hood for customer claim, repair authorization, rental, tow payment. 9. On site insurance adjuster: damage capture outside, policy rules + claim estimate inside. (I'll add more Duo ideas to and maybe talk more about it on @startupideaspod) Quick framework for finding iPhone Duo startup ideas (how I'd think about it): - A phone is great when the job starts in the real world: a photo, scan, call, message, location, or quick note. - An iPad is great when you sit down to create: draw, write, edit, design, review. - BUT, Duo is interesting in the messy middle: when someone starts with a phone, suddenly needs more space, has another person involved, AND there’s money or approval on the line. I think the best Duo ideas should feel weird on a normal iPhone and unnecessary on an iPad.