WHERE YOU ARE
Hold still — a first GPS fix can take a few minutes.
Emergency numbers normally connect from any phone that can see a network, including one with no SIM or no credit. They do not work with no network at all.
Your position keeps working when your phone has no signal. GPS listens to satellites; it needs no reception and no data. What it does need is sky — step out of the vehicle, away from cliffs and trees, and wait. Without a network to help it along, a cold fix takes one to five minutes.
If the readout above never leaves “Looking…”, the browser is refusing to ask
for your position. On Android there are three separate causes. Tapping the file in
Downloads or Files opens it at a content:// address, which is never given
GPS — open it from a folder so the address starts with file:///. Chrome
itself needs location permission from the phone: Settings › Apps › Chrome
› Permissions › Location. And the phone’s own Location switch, in Quick
Settings, has to be on. On an iPhone there are two switches, both required:
Settings › Privacy & Security › Location Services › Safari Websites
and Settings › Safari › Location.
The fallback works whatever the browser decides: press and hold the map where you are, or type coordinates into the search box, and this screen will read them back in large type. Check which of the two you have before you need it.
This app has no routing and no hospitals or police stations in it. Install a full offline map — Organic Maps or OsmAnd, with the Japan region downloaded — before you fly, and keep a paper note of where you are staying.
車中泊 (shachūhaku) means sleeping in your vehicle. It is ordinary and widely accepted in Japan, and it is the cheapest way to drive the country. It stays accepted because the people doing it are quiet, leave nothing behind, and do not treat a car park as a campsite.
Wash at the taps and rinse off completely before getting into the water — the bath is for soaking, not cleaning. No swimwear. Take the small towel in with you and leave the big one in the changing room. Tie up long hair. Tattoos are still refused at some places, so check at the desk if it matters.
Everything is in this one file — map, spots and text. It never contacts the network, so it works in a tunnel, in the mountains and on a dead SIM. The only buttons that need signal are the ones labelled as such.
Spots come from OpenStreetMap and are used here under the Open Database Licence. Names are shown in English where OpenStreetMap has one; otherwise they are romanised from the Japanese reading, and where there is no reading to work from the Japanese is kept as-is. The Japanese name is always shown too, because that is what is on the sign and what you can point at when asking directions. Coastlines and prefecture outlines are from Natural Earth, which is public domain.
The shaded parks are national, quasi-national and prefectural natural parks from the 国土数値情報 (National Land Numerical Information) survey published by Japan’s Ministry of Land, Infrastructure, Transport and Tourism, used here under its attribution and non-commercial terms. The survey is the 2010 edition, so parks designated since — Kerama Islands, Yanbaru, Amami Gunto — are not in it. Park names in English come from Wikidata (CC0), matched to each boundary by position; where no match was found the park is drawn without a label rather than guessed at.
Opening hours, fees and facilities are whatever OpenStreetMap recorded, which may be out of date or missing entirely. A blank field means nobody has mapped it, not that the thing is absent. Treat it all as a starting point and trust the sign in front of you over this app.