Yamajitaku (iOS / Android) / Last updated September 29, 2026
This is an English translation of the Japanese privacy policy. If the two differ, the Japanese version prevails.
None. There is no user information that the developer can obtain, store or view.
The trip plans, gear, meal plans, notes, body weight and anything else you enter in the app are all saved on the device you use. In the iOS version, if iCloud sync is turned on, they are also saved in your own iCloud account. Content saved in iCloud is on Apple’s service, and the developer cannot access it. The Android version has no iCloud sync, and data is saved only on the device.
Communication with outside services happens only in the following two cases. In neither case is information that identifies you sent.
When showing a weather forecast, the app sends the latitude, longitude and altitude of the selected mountain to Open-Meteo (an open-source weather API service). No information that could identify you, such as your name, device ID or account information, is sent. The developer does not store what is sent either. For Open-Meteo’s statement on privacy, please see their page.
Only when you use place-name search in “Find the mountain’s location” (山の位置を調べる) is the place name you enter sent to Open-Meteo’s place-name search API. If you do not use this feature, no communication takes place.
Camera permission is requested only when you use the feature for taking photos of your gear. A photo you take is only shrunk on the spot to 320 px square and saved on the device; the full-size photo is not kept. It is not sent outside either. Choosing a photo uses the device’s photo picker, so no permission to access your photo library is needed.
The climbing-plan feature lets you enter the names, ages, addresses, phone numbers, emergency contacts, blood types, mountaineering insurance and other details of yourself and your companions. These are saved on the device, just like your other trip data (and, in the iOS version with iCloud sync turned on, in your own iCloud as well), and are never sent to the developer or to third parties. A plan you create (PDF or text) is handed over only when you perform a share action, and only to the destination you choose (email, messages, printing and so on). If you enter information about your companions, please get their consent before entering it.
The reminder the day before departure, the reminder one hour before the check-in deadline, and the “until sunset” display on the day of a trip (a Live Activity on the Lock Screen in the iOS version, a notification in the Android version) are all scheduled and shown on the device. They do not go through any outside server. You can turn notifications off at any time in the device’s settings.
Data is saved on the device (and, in the iOS version with iCloud sync turned on, in your own iCloud as well). Deleting the app deletes the data on the device. In the iOS version, data left in iCloud can be deleted by removing the app’s entry under the device’s Settings → Apple ID → iCloud → iCloud Drive. In the Android version, deleting the app deletes the data on the device. If automatic backup was enabled, the copy on Google Drive can be deleted from Google Drive → Backups. You can also export a backup file from the app’s settings and keep it yourself.
This app is not aimed at any particular age group, and it does not collect personal information from users of any age.
Since no information is collected, there is no information to provide to third parties either. Information is never sold or shared.
The packing lists, warnings, weight estimates and weather forecasts shown by this app are guides based on general information. Their accuracy and completeness are not guaranteed. Final decisions and actions in the mountains are the responsibility of the user. The developer cannot accept responsibility for any damage arising from the use of this app.
If this policy is changed, this page will be updated and the last-updated date revised.
Please send questions about this policy to tatlink002@gmail.com.