This is what your traveller carries.

Not a mock-up. The phone beside this is the Travel Billy app itself, running on a made-up trip to Japan.

• Calendar — the trip day by day, built from the bookings rather than typed out.
• Documents — every ticket and voucher, sorted, and readable with no signal.
• Tools — where they land, local time, weather, packing and currency.
• Messages — a line straight back to you, kept with the trip.