Support
Contact for the KAIRAKU app
How to contact us
For questions, bug reports or requests about the app, please email us at:
FAQ
Q. Is the app free?
Yes. All features are free. A banner ad (Pangle) is shown at the bottom of the screen. There are no in-app purchases or subscriptions, and no account is needed.
Q. Which devices are supported?
iPhone and iPad with iOS 15.0 or later, and Android phones and tablets with Android 7.0 (API 24) or later.
Q. How do I change the personalized-ads setting?
Open "About this app" on the home screen and choose "Ad settings". On iOS, the setting in Settings > Privacy & Security > Tracking also applies.
Q. Do I need an internet connection?
Everything except ads, including all simulations and explanations, works offline. An internet connection is needed only to show ads.
Q. Can I use it in class?
Yes. Feel free to use it in schools, tutoring or self-study for educational purposes.
Q. How accurate is the oceanography?
The app is designed for middle school and high school earth science and biology through introductory university oceanography, and is based on models such as the UNESCO equation of state of seawater (EOS-80), the freezing point of seawater, Ekman transport, the tide-generating force, the linear wave dispersion relation and the shallow-water wave speed √(gh), the speed of sound in seawater, the 10% rule of food webs and the Degree Heating Weeks index for coral bleaching. Some details are simplified for clarity and so the simulations can run in real time. For professional or academic work, please also consult textbooks and the literature.
Q. Does it show real tide levels or tsunami warnings?
No. The app is an educational simulator for learning how the ocean works. It does not show real tide levels, sea conditions, tsunami warnings or observations. For safety decisions, please rely on official information from your national weather service and local authorities.
Q. What is the RAKU series?
SUUGAKU, BUTURAKU, DENRAKU, HARAKU, NETURAKU and others form a series of math and science simulation apps developed by Fuji Bit Inc. KAIRAKU is its oceanography edition.
Reporting a problem
When reporting a problem, the following information helps us fix it quickly.
- Your device model (e.g. iPhone 16)
- OS version (e.g. iOS 18.2 / Android 14)
- App version (e.g. 3.0.0)
- What happened and how to reproduce it
About the app
KAIRAKU is an ocean simulator for seeing how currents, waves, the deep sea and marine life work and trying it yourself. It has 12 modes: ocean layers, the global conveyor belt, the Ekman spiral, sea ice, tides, wave refraction and breaking, tsunamis, sound in the sea (the SOFAR channel), the marine food web, plankton blooms, coral bleaching and hydrothermal vents. It is available in 73 languages, including English and Japanese.
Version: 3.0.0