Telephone and Internet in Japan
How to use mobile terminal in Japan

97 percent of Japanese people own smartphone now.
Smartphones are now an essential part of daily life for Japanese people.
When you visit Japan, you will find that many people continue to operate smartphone in the train or on the road.
Therefore, the network environment is enough in Japan.
If you want to use your mobile terminal in Japan, check the way to do so on the official site of your telephone service company, first.
If it isn't enough, consider some following ways.
Prepaid-type SIM Card
This may be the newest cheap way to use mobile terminal in Japan.
If you want to use it cheaply and lightly in short duration, this is the best way.
Please check the following websites.
All of them are for foreign traveler.
Free Wi-Fi
Many Japanese people don't use free Wi-Fi very often.
Since mobile data is fast and reliable in Japan, people don't feel the need to use free Wi-Fi.
And, they are worried about the security risks of public Wi-Fi.
There are many places where you can use free Wi-Fi in Japan.
But it may not be good enough for you.
Japan Tourism Agency shows the info on the official website.
Rental Wi-Fi
If you want to use your mobile terminal heavily during your trip in Japan, renting a Wi-Fi router is an option.
Rental mobile phone and Wi-Fi
It is also a way to rent a mobile phone.
Public telephone

Public telephones in a railway station
If you don't have a mobile phone which is usable in Japan and you must make a call, go to a railroad station, a supermarket, a convenience store, a hotel, or a big hospital.
Maybe, you can find a public telephone there.
Of course, you can make a call from the room in the hotel where you are staying, but generally the telephone charge comes expensive by adding service charge and so on.
Therefore, I think you had better use public telephone.
You can use some coins or a telephone card (prepaid card) for calling.
Only 10 yen and 100 yen coins are available.
5 yen, 50 yen and 500 yen coins don't be accepted.
When you insert 10 yen, you can call for about 57 seconds within the city.
If a long‐distance call, the available time becomes short.
That’s why you shouldn't use it for long phone calls.
There are 500-yen telephone card and 1,000-yen telephone card, and the latter card is worth 1,050 yen.
You can buy them at a vending machine around the public telephone or covenience store.
During you call with telephone card, the balance is displayed.
Please check the following websites about public telephone.
There are two telephone companies (East Japan and West Japan), but the telephone set is the same.
You can make an international call from public telephones which display "International".
The international telephone service in Japan is offered by several companies.
But you have only to know the below "KDDI".