I am taking the opportunity to register my DJI Neo to fly in Japan to create this guide on registering a drone in Japan.
IMPORTANT INFO:
As one of the viewers, @youzaro, pointed out, this is a revised version of the video with revised information on Registration ID labeling.
Rules & Regulations
https://www.mlit.go.jp/en/koku/uas.html
1) Drone Maps Japan (iOS)
2) Sorapass (Android/iOS)
3) DJI FlySafe
4) GSI Japan