Support
Help, FAQ and contact for the CHIRAKU app
FAQ
Q. How do I use it?
Pick a simulation on the home screen and tap "Tap to start" in the middle of the screen. The dark band at the top shows "Phase N/4" and a one-line explanation of what is happening, and the four phases play in order. Use the ◀ ▶ buttons at the bottom to move between phases, and the "Speed" slider to set the pace from 0.5x to 3x. When the last phase is reached, the real-world example appears in an orange band and the simulation stops. Tap "Details" on the band to read the terms and formulas.
Q. What devices are supported?
iPhone and iPad with iOS 15.0 or later, and Android 7.0 (API 24) or later phones and tablets.
Q. Does it work offline?
All simulations work offline. The network is used only to deliver ads.
Q. Is it OK to use in classrooms?
Yes. Feel free to use it in schools, tutoring and personal study.
Q. How accurate are the simulations?
They use simplified, textbook-level models (Omori's formula, Jeffreys' equation, Stokes' law, Snell's law, a dipole magnetic field and so on). Do not use them for disaster preparation, earthquake forecasting or volcanic-activity assessment. Refer to official agencies (JMA in Japan, USGS, etc.) for real decisions.
Q. Are there in-app purchases or subscriptions?
No. All features are free. The app shows only a Pangle banner ad at the bottom of the screen.
Q. How do I turn off personalized ads?
Go to "About this app" > "Ad settings" in the app. On iOS you can also use Settings > Privacy & Security > Tracking. See the Privacy Policy for details.
Q. What information is sent?
The app itself has no accounts and no fields for personal information; it stores only your theme and ad choice on your device. To show ads, the ad SDK (Pangle) sends advertising identifiers, IP address, device information and similar data to Pangle. See Handling of Personal Information for details.
Bug reports
Please include the following when reporting an issue:
- Device model (e.g., iPhone 16, Pixel 10a)
- OS version (e.g., iOS 18.2 / Android 16)
- App version (e.g., 2.0.0)
- Which simulation
- Steps to reproduce and what you observed
About the app
CHIRAKU is an educational earth-science app with nine simulations: plate tectonics, seismic waves, epicenter location, volcanic eruption, lava flow, rock cycle, earth interior, geomagnetism and atmospheric circulation. Each runs in four phases and ends at a real-world example.
Languages: 16 — English, Japanese, Chinese (Simplified/Traditional), Korean, Spanish, Portuguese, German, French, Hindi, Indonesian, Russian, Italian, Turkish, Thai and Vietnamese (the app follows your device language; this website is in English and Japanese only).
Version: 2.0.0