Privacy Policy
This Privacy Policy sets out how GREENSTUDIO (the “Company”) handles users’ personal information or equivalent information in the application “Color Walker,” its related website, and related services (collectively, the “App”).
Article 1 Information We Collect
The Company may collect or use the following information to provide, maintain, and improve the App, prevent misuse, and respond to inquiries.
- Information entered or configured by users, such as display name, theme settings, and review-prompt management.
- Authentication and identification information necessary to use the App, such as anonymous user identifiers, session information, and join history.
- Account information provided by the linked service when a user links a Google or Apple account, such as an email address.
- Information entered or configured by users as their public profile, such as username, public name, bio, avatar color and icon, and social media account names.
- Information necessary to provide the Feed, such as images posted to the Feed, image metadata, notes, selected colors, public or private settings, likes, reactions, block settings, and report content.
- Information necessary to provide the in-app notification list, such as records of reactions to a user’s own posts.
- Information necessary to provide group features, such as group names, descriptions, join codes, join URL tokens, member information, posted images, image metadata, report content, and ban information.
- Information necessary to provide chat features, such as the body of chat messages, timestamps, sender identifiers, reactions, read positions, and settings for hiding specific members together with their display name at that time.
- Information necessary to deliver push notifications, such as device identifiers, notification destination identifiers, OS, the app’s display language, the device’s time zone, app version, notification permission status, and notification settings for each group and type.
- Information necessary to handle week changes and posting dates according to the date in the user’s region, such as the device’s time zone.
- Information necessary for incident investigation, security, and misuse prevention, such as access timestamps, communication logs, device information, user agent, IP address, and error information.
Article 2 Device Permissions and On-Device Data
To provide features such as shooting, image selection, collage creation, and group posting, the App may use permissions such as the camera, photo library, and device storage.
- Camera preview frames and collage creation are, in principle, processed on the device.
- Only images that the user posts, shares, or uploads are sent to the server.
- Images posted to a group or the Feed are re-encoded on the device before being sent. In this process, capture metadata (Exif), including information such as the capture location, is removed.
- Camera footage used to scan QR codes is processed on the device and is not sent to the server.
- Push notifications are sent only if the user has allowed notifications. Notification permission can be changed at any time in the OS settings, and the types of notifications in the in-app settings.
- The App does not use location, microphone, or contacts permissions. The device’s time zone is obtained as a region name (for example, Asia/Tokyo) and does not include information indicating the device’s location.
- Settings such as display name, theme settings, and review-prompt management may be stored in on-device storage.
- The body of chat messages is not stored on the device. Only some display settings, such as your reaction selection history, may be stored in on-device storage.
- Authentication information is stored in the device’s secure storage.
Article 3 Group Features, Posted Images, and Chat
In the App’s group features, users can take photos, post images, create and post collages, share images, fill the cells of a grid with photos in quests, and exchange messages via chat within groups they create or join.
- Images posted to a group are shared with members of the same group and may be viewed or downloaded.
- Posted images and image metadata are used for storage, display, distribution, thumbnail generation, deletion, incident investigation, report handling, and moderation.
- In quests, information such as which photo was placed in which cell, when a grid was completed, and the grid layout is stored and shown to members of the same group.
- Messages and reactions sent in chat are shared with members of the same group. For reactions, other members may be able to see which member added them.
- Messages do not store the sender’s display name; it is retrieved from the group membership information each time a message is displayed. As a result, changing your display name is also reflected in how your past messages are displayed.
- Messages, reactions, and read positions are used to provide, display, deliver, and delete chat features, and for incident investigation, report handling, and moderation.
- Third parties who receive a group’s join URL, join code, QR code, or similar may be able to access group information. Please manage this information at your own responsibility.
Article 4 Feed and Public Profiles
In the App’s Feed, users can post photos, view other users’ posts, and add likes and reactions. Unlike group information, information in the Feed and public profiles is made widely public.
- Posts made public in the Feed (images, notes, and selected colors) and public profiles (username, public name, bio, avatar, social media account names, and public posts) can be viewed by everyone who uses the App, including users who have not linked an account.
- Posts made with “Post privately” selected are not shown to anyone other than the poster.
- The number of likes, the number of reactions, and which users reacted may be visible to other users.
- Public profiles are managed separately from display names within groups. The names of groups a user belongs to are not shown on Feed posts or profiles.
- Block settings are used so that each party’s posts, reactions, and profile are not shown to the other. The blocked user is not notified.
- Reactions to a user’s own posts are recorded in order to notify the user through push notifications and the in-app notification list. Records in the notification list are deleted after a certain period.
- Feed posts, likes, reactions, and report content are used to provide, display, and deliver the Feed, and for thumbnail generation, deletion, incident investigation, report handling, and moderation.
- Information obtained through account linking, such as an email address, is used for authentication and account identification and is not shown to other users.
Article 5 Advertising
The App may use third-party advertising services. To display ads relevant to your interests, advertising services may use identifiers that do not directly identify individuals, such as advertising IDs.
Use of advertising IDs may be restricted or disabled by the user through the settings of iOS, Android, and each advertising service.
Article 6 Crash Reports and Incident Investigation
To improve the App’s stability, quickly fix bugs, and investigate incidents, the Company may collect or use information such as crash information, error information, communication logs, device information, and usage information.
We endeavor to handle this information in a form that does not directly identify individuals. However, we may review related information to the extent necessary for operations, such as responding to inquiries or investigating misuse.
Article 7 Authentication Information
To provide features such as groups and the Feed, the App uses authentication information such as anonymous user identifiers, session information, and, where a Google or Apple account is linked, information about the linked account.
- Communications use encrypted channels.
- When the app uses authentication information, it uses the device’s secure storage areas, such as the keychain or encrypted storage.
- Authentication information is used for App-specific data storage, group participation, posting, history retrieval, and misuse prevention.
Article 8 Storage and Deletion of App Data
App-specific data used in the App may be stored in on-device storage and on the server. On the server side, data may be stored or processed using cloud infrastructure.
- Users may request to review or delete data through in-app actions, deleting data on the device, uninstalling the App, or contacting us.
- Posted images, group information, Feed posts, chat messages, join history, report content, ban information, and similar data may be retained for a certain period to the extent necessary for legal compliance, misuse prevention, incident investigation, and service operations.
- Data such as groups, posted images, Feed posts, chat messages, and join history may be deleted due to the passage of the retention period, host actions, report handling, moderation, or operational reasons.
- Users can delete their own Feed posts at any time. A deleted post immediately becomes unavailable to other users, but it may take some time for the image to be completely deleted from the server.
- If you delete your account, your public profile, Feed posts, likes, and reactions are deleted. However, to prevent impersonation, the username you were using is retained for a certain period in a state that other users cannot use.
- A deleted message immediately becomes unavailable to other members, but a record used to preserve message ordering may remain for a certain period. This record does not include the message body.
- If you delete your account or your data, the body of your chat messages is deleted, but the process may take some time to complete.
- Records relating to reports may be retained for the purposes of moderation and misuse prevention, even after the message, image, post, group, or account concerned has been deleted.
Article 9 Provision to Third Parties and External Services
The Company does not provide collected information to third parties, except where required by law, where the user consents, where external services necessary to provide the App are used, or where necessary for misuse prevention and security.
The App may integrate with the App Store, Google Play, operating systems, browsers, cloud services, advertising services, and other external services. The handling of information in external services follows the terms and privacy policies of each provider.
Article 10 Suspension and Moderation
Where there is inappropriate posting, nuisance, misuse, violation of law, violation of the Terms, or other cases the Company deems necessary, the Company may, without prior notice, take measures such as deleting posts, restricting group participation, banning, or suspending use.
The Company may review report content, posted content, chat content, public profile content, usage, communication logs, and other necessary information to carry out moderation and anti-misuse measures. The Company may also decline to individually disclose the reasons for suspension or moderation decisions.
The Company does not constantly monitor the content of chat or the Feed. Where the Company becomes aware of a problem through a report or otherwise, it reviews the content to the extent it deems necessary.
Article 11 Changes to the Privacy Policy
The Company may revise this Privacy Policy as necessary. The revised Privacy Policy takes effect when displayed on this website or within the App.
Article 12 Contact
For questions about this Privacy Policy, please reach out via the contact page.
Last updated: October 4, 2026