Traveler builds a Claude-powered Japan trip app with email scanning, photo help and low-walking mode
Greengage1 · reddit · 2026-10-16
A user details using Claude (Opus 5.5) to plan a Japan trip and build a custom travel companion app. Claude's first draft already included itinerary, shopping list, bookings, tailored phrases and Japanese location cards for taxi drivers; iteration added far more:
- Google Maps links, step-by-step directions (which exit, which elevator), travel times, and suggested morning departure times
- Email scanning for booking references, check-in times, breakfast details, with links to each email
- Shopping items matched to each day's route; dinner suggestions by regional specialty within walking distance
- A low-walking mode toggle that refactors each day's plan with km estimates for both modes
- A photo-based 'ask' tab: translate menus, get guidance on ticket machines, or just ask questions
- Continuous inbox monitoring that auto-translated Japanese emails and drafted replies
The killer feature: free-form questions over all that context — recovering from a missed train, swapping a tiring activity, or calculating how much yen to load. Nearly zero significant errors across the trip.
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