Here you will find the answers and hopefully this can help you who want to go to Japan.
The first thing you should do is of course determine the location you want to go. Example: Kiyomizu-dera Temple, Osaka Castle, Disney Sea, and others.
After that, what most important thing you have to do is order a mobile WiFi to use during your stay in Japan. Why I ask you to have mobile WiFi while in Japan, because it is very difficult to find free WiFi while you are on the road or public area and of course you will need the internet. Most free WiFi just being in a hotel room.
I’m sorry I did not make a comparison to some companies because I did not have much time. When I searched in Google, It showed this website : http://www.globaladvancedcomm.com. And I was satisfied with this company. The rental price wasn’t too expensive ( for me), and the internet speed was very remarkable even used for 4-5 gadgets at once.
There was no buffering at all. Loved the internet speed so much.