1. Definitions
"Service" means the SaQura Messenger application, including the iOS mobile application, web application, server infrastructure, and all related services operated by the Company.
"Company," "we," "us," or "our" means KyotoTech LLC (合同会社KyotoTech), a Japanese limited liability company registered in Kyoto, Japan.
"User," "you," or "your" means any individual who creates an account or uses the Service.
"Content" means any text, images, videos, audio, files, documents, or other materials transmitted, stored, or shared through the Service.
"Encryption Keys" means the RSA, AES, and quantum-safe cryptographic keys generated on your device and used to encrypt and decrypt Content.
"End-to-End Encryption" (E2EE) means the encryption method where Content is encrypted on the sender's device and can only be decrypted on the recipient's device. The Company cannot access or read encrypted Content.
"Account" means the registered user profile required to access and use the Service.
2. Acceptance of Terms
By downloading, installing, creating an account, or using the Service in any manner, you acknowledge that you have read, understood, and agree to be bound by these Terms of Service.
IF YOU DO NOT AGREE TO ALL OF THESE TERMS, YOU MUST NOT USE THE SERVICE. YOUR USE OF THE SERVICE CONSTITUTES YOUR BINDING ACCEPTANCE OF THESE TERMS.
If you are accepting these Terms on behalf of a company, organization, or other legal entity, you represent and warrant that you have the authority to bind such entity to these Terms.
3. Eligibility
You must be at least 16 years old to use the Service. If you are under the age of legal majority in your jurisdiction, you may only use the Service with the consent and supervision of a parent or legal guardian who agrees to be bound by these Terms.
You may not use the Service if:
- You have been previously suspended or permanently banned from the Service
- You are located in a country subject to comprehensive sanctions
- You are prohibited from receiving the Service under applicable laws
4. Account Registration
Account Creation
To use the Service, you must create an account by providing a valid email address and creating a password, or by authenticating through a supported third-party provider (Apple ID, Google). You agree to provide accurate and complete information.
Account Security
You are solely responsible for:
- Maintaining the confidentiality of your account credentials
- All activities that occur under your account
- Immediately notifying us of any unauthorized use of your account
WE ARE NOT LIABLE FOR ANY LOSS OR DAMAGE ARISING FROM YOUR FAILURE TO MAINTAIN THE SECURITY OF YOUR ACCOUNT CREDENTIALS.
One Account Per Person
Each individual may maintain only one account. We reserve the right to terminate duplicate accounts without notice.
5. Service Description
SaQura Messenger is an end-to-end encrypted messaging application that enables users to exchange text messages, images, videos, voice messages, files, and make voice/video calls. The Service includes:
- Direct and group messaging with end-to-end encryption
- Media sharing (photos, videos, documents, voice messages)
- Voice and video calling (WebRTC)
- Stories
- Polls and location sharing
- Contact management and workspaces
- Optional quantum-safe encryption
The Service is provided on an "as available" basis. Features may be added, modified, or removed at any time without prior notice.
6. Subscription Plans & Payment
Free Tier
The Service offers a free tier with basic messaging functionality. Free accounts may be subject to feature limitations as described on our website.
Paid Subscriptions
Paid subscription plans (Private, Business) are available exclusively through our website at saqura.kyototech.co.jp. Subscriptions are NOT available as in-app purchases.
Payment Processing
Payments are processed by Stripe, Inc., a third-party payment processor. By subscribing, you also agree to Stripe's terms of service. We do not store your credit card information.
Billing & Renewal
- Subscriptions are billed on a recurring monthly basis
- Subscriptions automatically renew unless cancelled before the end of the current billing period
- Prices may change with 30 days' advance notice
Refunds
ALL SUBSCRIPTION FEES ARE NON-REFUNDABLE, except as required by applicable law or at our sole discretion. Downgrading or cancelling a subscription does not entitle you to a refund for the current billing period.
7. Acceptable Use Policy
PROHIBITED ACTIVITIES
Violation of this policy may result in immediate account termination without notice or refund.
You must NOT use the Service to:
- Transmit any Content that is unlawful, harmful, threatening, abusive, harassing, defamatory, vulgar, obscene, or otherwise objectionable
- Distribute child sexual abuse material (CSAM) or exploit minors in any way
- Engage in terrorism, incite violence, or promote extremist ideologies
- Distribute malware, viruses, or other harmful software
- Conduct fraud, phishing, or social engineering attacks
- Infringe upon intellectual property rights of third parties
- Violate any applicable local, national, or international law or regulation
- Impersonate any person or entity, or falsely state or misrepresent your identity
- Collect, harvest, or store personal data of other users without their consent
- Send unsolicited bulk messages (spam)
- Attempt to gain unauthorized access to the Service, other user accounts, or related systems
- Reverse engineer, decompile, or disassemble any part of the Service
- Circumvent, disable, or interfere with security features of the Service
- Use the Service for illegal drug trafficking, money laundering, or financing of criminal activities
- Use automated systems, bots, or scripts to interact with the Service
- Resell, redistribute, or sublicense access to the Service
We reserve the right to investigate and take appropriate action, including but not limited to reporting to law enforcement authorities, with respect to conduct that violates this policy.
8. User Content & Conduct
Ownership
You retain ownership of Content you create and transmit through the Service. By using the Service, you grant us a limited, non-exclusive license to process, transmit, and temporarily store your Content solely for the purpose of providing the Service.
Content Responsibility
YOU ARE SOLELY AND ENTIRELY RESPONSIBLE FOR ALL CONTENT THAT YOU TRANSMIT, SHARE, OR STORE THROUGH THE SERVICE. Due to end-to-end encryption, we cannot monitor, review, or filter the content of your messages.
No Obligation to Monitor
Because the Service uses end-to-end encryption, we are technically unable to access, read, or monitor the content of your encrypted communications. We have no obligation to monitor Content and accept no liability whatsoever for any Content transmitted through the Service.
Reporting
If you receive Content that you believe violates these Terms or applicable law, you may report the sender's account to us. We may take action on reported accounts at our sole discretion.
9. End-to-End Encryption & Key Management
CRITICAL WARNING - READ CAREFULLY
Encryption Key Responsibility
YOUR ENCRYPTION KEYS ARE GENERATED AND STORED EXCLUSIVELY ON YOUR DEVICE(S). YOU ARE SOLELY AND ENTIRELY RESPONSIBLE FOR:
- The security, backup, and management of your Encryption Keys
- Using the optional key backup feature to protect against key loss
- Maintaining access to your device(s) where keys are stored
No Key Access by Company
KYOTOTECH LLC DOES NOT HAVE ACCESS TO, STORE, OR MAINTAIN COPIES OF YOUR ENCRYPTION KEYS. We have NO TECHNICAL CAPABILITY to decrypt your messages, recover your keys, or access your encrypted Content under any circumstances.
Permanent Data Loss
IF YOU LOSE ACCESS TO YOUR ENCRYPTION KEYS:
- YOUR ENCRYPTED MESSAGE HISTORY WILL BE PERMANENTLY AND IRREVERSIBLY INACCESSIBLE
- KyotoTech LLC CANNOT AND WILL NOT recover your data under any circumstances, including upon court order, subpoena, or any other legal process
- You will have NO LEGAL RECOURSE against KyotoTech LLC for such data loss
BY USING THE SERVICE, YOU ACKNOWLEDGE AND ACCEPT THAT YOU HAVE READ, UNDERSTOOD, AND ACCEPTED THE RISKS OF END-TO-END ENCRYPTION AS DESCRIBED IN THIS SECTION.
Encryption Technology
The Service uses RSA-4096, AES-256-GCM, and optional quantum-safe encryption algorithms. We do not warrant that these cryptographic methods are or will remain secure against all current or future attacks.
Law Enforcement Access
Due to the end-to-end encrypted nature of the Service, we are technically unable to provide the content of encrypted messages to any third party, including law enforcement agencies. We may be able to provide non-content metadata (e.g., account registration information, IP addresses, timestamps) in response to valid legal process.
10. Data Handling & Privacy
Privacy Policy
Our collection and use of personal data is governed by our Privacy Policy, which is incorporated into these Terms by reference.
Data We Process
To provide the Service, we process:
- Account data: Email address, display name, avatar, SaQura ID
- Encrypted message data: Encrypted content (which we cannot read), metadata (timestamps, sender/recipient IDs, message type)
- Device data: Device identifier, platform, push notification tokens
- Usage data: Last seen status, online status, read receipts
- Public keys: Your public encryption keys (shared with other users for E2EE)
Data We Cannot Access
Due to end-to-end encryption, we cannot access:
- The plaintext content of messages
- Photos, videos, voice messages, or files shared between users
- Your private encryption keys
Server Storage
Encrypted messages are stored on our servers to enable message delivery and synchronization across devices. Users may disable server-side message storage in their settings, in which case messages are deleted from our servers after delivery.
Data Location
Our servers are located in Japan. By using the Service, you consent to the processing and storage of your data in Japan.
GDPR (European Economic Area Users)
If you are located in the European Economic Area, you have rights under the General Data Protection Regulation (GDPR), including the right to access, rectify, delete, and port your personal data. Please see our Privacy Policy for details on exercising your rights.
APPI (Japanese Users)
Our data processing complies with Japan's Act on the Protection of Personal Information (個人情報の保護に関する法律). See our Privacy Policy for details.
11. Service Availability
NO GUARANTEE OF AVAILABILITY
THE SERVICE IS PROVIDED ON AN "AS AVAILABLE" BASIS. WE DO NOT GUARANTEE UNINTERRUPTED, TIMELY, SECURE, OR ERROR-FREE OPERATION.
Service Interruptions
We may, without prior notice or liability:
- Modify, suspend, or discontinue any part of the Service at any time
- Perform scheduled or unscheduled maintenance
- Impose limits on certain features or restrict access to parts of the Service
No SLA
WE PROVIDE NO SERVICE LEVEL AGREEMENT (SLA) AND MAKE NO COMMITMENT REGARDING UPTIME, AVAILABILITY, OR RESPONSE TIME. You acknowledge that the Service may experience outages, and you shall not have any claim against us for any such outage or interruption.
No Emergency Services
THE SERVICE IS NOT INTENDED OR DESIGNED FOR USE IN EMERGENCIES. DO NOT RELY ON THE SERVICE AS YOUR SOLE MEANS OF COMMUNICATION. The Service does not support emergency calls (e.g., 110, 119, 911, 112).
12. Third-Party Services
The Service may integrate with or rely upon third-party services, including but not limited to:
- Apple Sign-In / Google Sign-In: For authentication
- Stripe: For payment processing
- Apple Push Notification service (APNs): For push notifications
WE ARE NOT RESPONSIBLE FOR THE AVAILABILITY, SECURITY, ACCURACY, OR PRACTICES OF ANY THIRD-PARTY SERVICES. Your use of third-party services is governed by their respective terms of service and privacy policies.
13. Intellectual Property
Ownership
The Service, including all software, design, text, graphics, logos, icons, and the underlying SaQura encryption technology, is the exclusive property of KyotoTech LLC and is protected by copyright, trademark, and other intellectual property laws.
Limited License
We grant you a limited, non-exclusive, non-transferable, revocable license to use the Service for personal, non-commercial purposes in accordance with these Terms.
Restrictions
You may not:
- Copy, modify, or create derivative works based on the Service
- Reverse engineer, decompile, or disassemble the Service
- Remove or alter any proprietary notices or labels
- Use "SaQura" or "KyotoTech" trademarks without written permission
Feedback
Any feedback, suggestions, or ideas you provide regarding the Service become the property of KyotoTech LLC, and you assign all rights therein to us.
14. Warranty Disclaimer
DISCLAIMER OF ALL WARRANTIES
THE SERVICE IS PROVIDED "AS IS," "AS AVAILABLE," AND "WITH ALL FAULTS." TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, KYOTOTECH LLC AND ITS DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, AFFILIATES, SUPPLIERS, AND LICENSORS EXPRESSLY DISCLAIM ALL WARRANTIES, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING BUT NOT LIMITED TO:
- IMPLIED WARRANTIES OF MERCHANTABILITY
- FITNESS FOR A PARTICULAR PURPOSE
- NON-INFRINGEMENT
- TITLE
- ACCURACY, RELIABILITY, OR COMPLETENESS
- THAT THE SERVICE WILL BE UNINTERRUPTED, TIMELY, SECURE, OR ERROR-FREE
- THAT DEFECTS WILL BE CORRECTED
- THAT THE SERVICE IS FREE OF VIRUSES OR OTHER HARMFUL COMPONENTS
- THAT MESSAGES WILL BE DELIVERED SUCCESSFULLY OR IN A TIMELY MANNER
- THAT ENCRYPTION WILL PROTECT AGAINST ALL ATTACKS OR INTERCEPTION
- THAT YOUR DATA WILL NOT BE LOST, CORRUPTED, OR DESTROYED
Cryptographic Security
WE DO NOT WARRANT THAT:
- The encryption algorithms used are or will remain secure against all current or future attacks, including quantum computing attacks
- The Service meets any specific security certification or compliance standard
- The quantum-safe encryption features provide guaranteed protection against future quantum computers
- The end-to-end encryption implementation is free from vulnerabilities
YOU USE THE SERVICE ENTIRELY AT YOUR OWN RISK. YOU ASSUME FULL RESPONSIBILITY FOR ANY CONSEQUENCES ARISING FROM YOUR USE OF THE SERVICE.
15. Limitation of Liability
PLEASE READ THIS SECTION CAREFULLY. IT LIMITS THE LIABILITY OF KYOTOTECH LLC.
Exclusion of Damages
TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT SHALL KYOTOTECH LLC, ITS DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, AFFILIATES, SUPPLIERS, OR LICENSORS BE LIABLE TO YOU OR ANY THIRD PARTY FOR:
- ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES
- LOSS OF DATA, MESSAGES, OR CONTENT, INCLUDING ENCRYPTED DATA THAT BECOMES INACCESSIBLE
- LOSS OF PROFITS, REVENUE, BUSINESS, GOODWILL, OR ANTICIPATED SAVINGS
- BUSINESS INTERRUPTION OR LOSS OF BUSINESS OPPORTUNITIES
- COST OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES
- UNAUTHORIZED ACCESS TO, INTERCEPTION OF, OR ALTERATION OF YOUR TRANSMISSIONS OR DATA
- SECURITY BREACHES, HACKING, OR UNAUTHORIZED ACCESS TO YOUR ACCOUNT
- ANY FAILURE OF ENCRYPTION TO PROTECT YOUR DATA
- LOSS OR COMPROMISE OF ENCRYPTION KEYS
- ACTIONS OR CONTENT OF OTHER USERS
- SERVICE INTERRUPTIONS, DOWNTIME, OR UNAVAILABILITY
- FAILED OR DELAYED MESSAGE DELIVERY
- ANY CONDUCT OR CONTENT OF ANY THIRD PARTY
- DAMAGES ARISING FROM YOUR FAILURE TO MAINTAIN ADEQUATE SECURITY MEASURES
REGARDLESS OF THE THEORY OF LIABILITY (CONTRACT, TORT, STRICT LIABILITY, NEGLIGENCE, OR OTHERWISE), EVEN IF WE HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Liability Cap
IF, NOTWITHSTANDING THE FOREGOING EXCLUSIONS, KYOTOTECH LLC IS FOUND LIABLE TO YOU FOR ANY CAUSE WHATSOEVER, OUR TOTAL AGGREGATE LIABILITY SHALL NOT EXCEED THE GREATER OF:
- THE TOTAL AMOUNT YOU HAVE PAID TO US FOR THE SERVICE IN THE SIX (6) MONTHS IMMEDIATELY PRECEDING THE EVENT GIVING RISE TO THE CLAIM; OR
- FIFTY US DOLLARS (USD $50)
Exceptions
The limitations in this section shall not apply to:
- Liability arising from our gross negligence (重過失) or willful misconduct (故意) under Japanese law
- Liability that cannot be excluded or limited under applicable mandatory law
Japan Consumer Contract Act
If you are a consumer as defined under Japan's Consumer Contract Act (消費者契約法), certain limitations may not apply to the extent prohibited by that Act. In such cases, our liability shall be limited to the minimum extent permitted by law.
Acknowledgment
YOU ACKNOWLEDGE THAT THE LIMITATIONS OF LIABILITY IN THIS SECTION ARE A FUNDAMENTAL ELEMENT OF THE BASIS OF THE BARGAIN BETWEEN YOU AND KYOTOTECH LLC, AND THAT KYOTOTECH LLC WOULD NOT PROVIDE THE SERVICE WITHOUT SUCH LIMITATIONS.
16. Indemnification
YOU AGREE TO INDEMNIFY, DEFEND, AND HOLD HARMLESS KyotoTech LLC, its directors, officers, employees, agents, affiliates, successors, and assigns from and against any and all claims, damages, losses, liabilities, costs, and expenses (including reasonable attorneys' fees and court costs) arising from or related to:
- Your use of, or inability to use, the Service
- Any Content you transmit, store, or share through the Service
- Your violation of these Terms
- Your violation of any applicable law, regulation, or third-party right
- Your negligence, willful misconduct, or fraudulent activity
- Any dispute between you and another user of the Service
- Your failure to properly manage or secure your Encryption Keys
- Your failure to maintain the security of your account
- Any claim arising from Content you transmitted through the Service
This indemnification obligation shall survive the termination of your account and these Terms.
17. Termination & Account Deletion
Termination by You
You may terminate your account at any time by using the account deletion feature within the application or by contacting us. Account deletion is subject to a 30-day grace period during which you may cancel the deletion.
Termination by Us
We may, at our sole discretion and without prior notice, immediately suspend, restrict, or permanently terminate your account and access to the Service for any reason, including but not limited to:
- Violation of these Terms or the Acceptable Use Policy
- Illegal activity or suspected illegal activity
- Requests by law enforcement or government agencies
- Extended periods of inactivity
- Technical or security issues
- Non-payment of subscription fees
- Any other reason at our sole discretion
Effect of Termination
Upon termination:
- Your license to use the Service immediately terminates
- Your account data will be deleted in accordance with our data retention policies
- Encrypted messages stored on our servers will be deleted
- Active subscriptions are not refunded upon termination for cause
- Sections 8-16 (Content, Encryption, Warranty, Liability, Indemnification) and 20-22 (Governing Law, Class Action, General) survive termination
Data Portability
You may export your data before account deletion using the backup feature in the application settings. After account deletion, your data cannot be recovered.
18. Export Control Compliance
CRYPTOGRAPHIC SOFTWARE EXPORT REGULATIONS
The Service contains cryptographic technology that may be subject to export controls under the Wassenaar Arrangement and national implementations thereof.
You represent and warrant that:
- You will comply with all applicable export control laws and regulations, including Japan's Foreign Exchange and Foreign Trade Act (外国為替及び外国貿易法)
- You will not use the Service in any country subject to comprehensive sanctions
- You will not use the Service for any purpose prohibited by export control laws, including the development, design, manufacture, or production of nuclear, chemical, or biological weapons
You agree to indemnify and hold harmless the Company from any claims, damages, or penalties arising from your violation of export control laws.
19. Modifications to Terms
We reserve the right to modify these Terms at any time. We will notify you of material changes by:
- Posting the updated Terms on our website
- Displaying a notice within the application
- Updating the "Effective Date" at the top of this document
- For significant changes, sending an email to your registered address
Your continued use of the Service after the effective date of any modifications constitutes your acceptance of the modified Terms. If you do not agree to the modified Terms, you must stop using the Service and delete your account.
20. Governing Law & Dispute Resolution
Governing Law
These Terms shall be governed by and construed in accordance with the laws of Japan, without regard to its conflict of law principles.
Jurisdiction
Any dispute arising out of or relating to these Terms or the Service shall be subject to the exclusive jurisdiction of the Kyoto District Court (京都地方裁判所) as the court of first instance.
Force Majeure
Neither party shall be liable for any failure or delay in performance due to circumstances beyond its reasonable control, including but not limited to acts of God, natural disasters, war, terrorism, civil unrest, government actions, epidemics, pandemics, power outages, internet disruptions, cyberattacks, or failure of third-party services (including Apple, Google, Stripe, or hosting providers).
21. Class Action Waiver
PLEASE READ THIS SECTION CAREFULLY. IT AFFECTS YOUR LEGAL RIGHTS.
Waiver of Class and Collective Actions
TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, YOU AND KYOTOTECH LLC AGREE THAT ANY DISPUTES SHALL BE RESOLVED ON AN INDIVIDUAL BASIS ONLY.
YOU EXPRESSLY WAIVE ANY RIGHT TO:
- Participate in a class action, collective action, or representative action against KyotoTech LLC
- Participate in class-wide arbitration or any arbitration involving joint or consolidated claims
- Act as a private attorney general or in any other representative capacity
Jury Trial Waiver
TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, YOU AND KYOTOTECH LLC WAIVE ANY RIGHT TO A JURY TRIAL.
Opt-Out Right (U.S. Users)
If you are located in the United States, you may opt out of this Class Action Waiver by sending written notice to support@kyototech.co.jp within thirty (30) days of first accepting these Terms.
22. General Provisions
Entire Agreement
These Terms, together with the Privacy Policy, constitute the entire agreement between you and KyotoTech LLC regarding the Service.
Severability
If any provision of these Terms is found to be invalid, illegal, or unenforceable, the remaining provisions shall continue in full force and effect.
Waiver
Our failure to enforce any provision shall not constitute a waiver of that or any other provision.
Assignment
You may not assign or transfer these Terms or your rights hereunder without our prior written consent. We may assign these Terms without restriction, including in connection with a merger, acquisition, or sale of assets.
No Agency
Nothing in these Terms creates any agency, partnership, joint venture, or employment relationship.
Notices
Notices to us should be sent to support@kyototech.co.jp. Notices to you will be sent to the email address associated with your account or displayed within the application.
Language
These Terms are provided in English. In the event of any conflict between translated versions and the English version, the English version shall prevail.
23. Contact Information
Company Information
KyotoTech LLC (合同会社KyotoTech)
〒612-8083 京都市伏見区京町2丁目237-202
Kyoto, Japan
Contact
Related Documents
Version History
| Version |
Date |
Changes |
| 1.0 | March 15, 2026 | Initial release |