1. Definitions
"Service" means SaQura Messenger: the mobile applications published by the Company (shown in the app stores as "SaQura"), the delivery server ("relay") operated by the Company, and all related services.
"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 installs or uses the Service.
"Identity" means the cryptographic key pair that the app creates on your device when you first set it up. It takes the place of a user account. No e-mail address, phone number or registration is required.
"Content" means any text, images, videos, audio, files, documents, or other materials transmitted, stored, or shared through the Service.
"Encryption Keys" means the cryptographic keys used to encrypt and decrypt Content, including your Identity keys.
"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 recipients' devices. The Company does not hold the keys needed to read encrypted Content.
"App Store" means the store through which you obtained the app, such as the Apple App Store or Google Play.
"Organization" means a company or public body that provides the Service to its members, either hosted by the Company or on its own server ("self-hosting").
2. Acceptance of Terms
By downloading, installing, setting up an Identity, 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.
The license terms of your App Store apply in addition to these Terms. This includes Apple's Licensed Application End User License Agreement for apps obtained from the Apple App Store.
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. Your Identity and Devices
No Account
The Service works without a user account. When you first open the app, you choose a display name and the app creates your Identity on your device. We do not ask for an e-mail address or a phone number.
Your Responsibility
You are solely responsible for:
- Keeping your device and its unlock method (passcode, biometrics) secure
- Keeping your recovery phrase safe and private
- All activities carried out with your Identity
WE ARE NOT LIABLE FOR ANY LOSS OR DAMAGE ARISING FROM YOUR FAILURE TO KEEP YOUR DEVICE OR YOUR RECOVERY PHRASE SECURE.
Additional Devices
You can move to a new device or add a second one by pairing the devices directly with each other. Each device receives its own Identity.
Use Within an Organization
If you use the Service as a member of an Organization, that Organization may set rules for your use, enable or disable features, and manage your membership. Where an Organization runs the Service on its own server, the Organization operates that server and is responsible for it.
5. Service Description
SaQura Messenger is an end-to-end encrypted messenger. Your messages and media are stored encrypted on your device, and our relay forwards them in encrypted form. The Service includes:
- Direct and group messaging with end-to-end encryption
- Sharing of photos, videos, files and voice messages
- Voice and video calls
- Separate personal and business areas in one app
- Encrypted backup with a recovery phrase and direct device-to-device migration
- Live location sharing, when you start it yourself
- Use within Organizations, hosted by us or on the Organization's own server
Which features and platforms are available depends on your App Store, your region, your app version and your plan. 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 Use
The basic functions of the Service, including end-to-end encrypted messaging and groups, can be used free of charge.
SaQura Pro
Additional functions are available with an optional subscription called "SaQura Pro". It is offered as an in-app purchase with a monthly or a yearly term. The app shows the functions included, the term and the price before you buy.
Payment Processing
In-app purchases are sold and billed by your App Store (Apple or Google) through the payment method stored there. The terms of your App Store apply to the purchase. We receive a proof of purchase to unlock the functions. We do not receive your payment details.
Billing & Renewal
- A subscription renews automatically for the same term unless you cancel it at least 24 hours before the end of the current term
- You manage and cancel your subscription in the account settings of your App Store. Deleting the app does not cancel a subscription
- After cancellation, the Pro functions remain available until the end of the term already paid for
- The price shown in your App Store at the time of purchase applies. Price changes are announced by your App Store under its rules
Refunds
Refunds for in-app purchases are handled by your App Store under its refund rules. We cannot issue refunds for purchases made there. Rights that you have under mandatory consumer law remain unaffected.
Organizations
Organizations obtain the Service under a separate agreement with us. That agreement governs fees, payment and term for the Organization and its members.
7. Acceptable Use Policy
PROHIBITED ACTIVITIES
Violation of this policy may result in immediate termination of your access 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, the devices or data of other users, 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 transmit and temporarily store your Content in encrypted form 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 do not hold the keys needed to 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 it to us at support@kyototech.co.jp. We may take action on reports at our sole discretion, for example by blocking a device from our relay.
9. End-to-End Encryption & Key Management
CRITICAL WARNING - READ CAREFULLY
Encryption Key Responsibility
Your Encryption Keys are created on your device and stay on the devices of the participants. Your Identity key is protected by the secure hardware of your device. An encrypted backup can only be restored with your recovery phrase.
YOU ARE SOLELY AND ENTIRELY RESPONSIBLE FOR:
- Creating a backup and keeping your recovery phrase safe
- Maintaining access to the device(s) where your keys and messages are stored
- Checking the safety number of a contact where you need certainty about who you are talking to
No Key Access by Company
KYOTOTECH LLC DOES NOT HOLD YOUR PRIVATE KEYS OR YOUR RECOVERY PHRASE. We cannot decrypt your messages, and we cannot recover your keys or your recovery phrase for you.
Permanent Data Loss
IF YOU LOSE YOUR DEVICE, DELETE THE APP, OR DELETE YOUR IDENTITY WITHOUT A BACKUP AND RECOVERY PHRASE:
- YOUR MESSAGE HISTORY WILL BE PERMANENTLY AND IRREVERSIBLY INACCESSIBLE
- KyotoTech LLC CANNOT recover your data under any circumstances, including upon court order, subpoena, or any other legal process
- To the extent permitted by law, you have no claim 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 encrypts messages, media and calls with the Messaging Layer Security standard (MLS, RFC 9420) combined with a hybrid post-quantum scheme. Data stored on your device is encrypted with AES-256-GCM. 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 do not hold the keys needed to provide the content of encrypted messages to any third party, including law enforcement agencies. In response to valid legal process we can only provide the limited technical data our relay holds, as described in Section 10.
10. Data Handling & Privacy
Privacy Policy
Our handling of personal data in the Service is described in the SaQura Messenger Privacy Policy, which is incorporated into these Terms by reference.
Data on Your Device
Your Identity, messages, chats, contacts, media and settings are stored on your device in encrypted form. We have no access to them.
Data Our Relay Processes
To deliver your messages, our relay processes only what is technically needed:
- Encrypted message envelopes: held in a form we cannot read and deleted after delivery
- Encrypted large media: larger attachments are held end-to-end encrypted so that recipient devices can fetch them, and are deleted automatically after a fixed period. The key travels only inside the encrypted message and never reaches our server
- Delivery data: a pseudonymous device fingerprint derived from your public key and a push token, so that messages reach the right device
- Usage counters for Organizations: monthly totals without content, for capacity and license management
- Proof of purchase: a transaction identifier from your App Store when you buy SaQura Pro
What We Do Not Do
The Service contains no advertising and no third-party advertising or analytics tools. We do not upload your address book. Diagnostic reports stay on your device and are sent to our support only when you choose to send them.
Data Location
The relay operated by us is hosted in Germany. Push notifications and in-app purchases run through the infrastructure of Apple or Google. Where an Organization runs its own server, that Organization decides where its data is processed.
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 the SaQura Messenger Privacy Policy for details on exercising your rights.
APPI (Japanese Users)
We design our data processing to meet Japan's Act on the Protection of Personal Information (個人情報の保護に関する法律). See the SaQura Messenger 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 relies on third-party services, including:
- Apple App Store and Google Play: For distributing the app and for in-app purchases
- Apple Push Notification service (APNs) and Firebase Cloud Messaging (Google): For push notifications. Push messages carry no readable message content
- Hosting provider: For operating our relay in Germany
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 post-quantum 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 DEVICE OR IDENTITY
- 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 device or recovery phrase
- Any claim arising from Content you transmitted through the Service
This indemnification obligation shall survive the termination of your use of the Service and these Terms.
17. Termination & Deletion
Termination by You
You may stop using the Service at any time. In the app you can delete all local data, or delete your Identity together with all data. Deleting your Identity destroys the local key, so the data cannot be restored afterwards. A running subscription must be cancelled separately in your App Store.
Termination by Us
We may suspend, restrict, or permanently end your access to our relay, for reasons 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
- Technical or security issues
- The end of an Organization's agreement through which you use the Service
Effect of Termination
Upon termination:
- Your license to use the Service ends
- Data held for your device on our relay is deleted in accordance with our retention periods
- Data on your device stays there until you delete it
- Refunds for subscriptions follow the rules of your App Store
- Sections 8-16 (Content, Encryption, Warranty, Liability, Indemnification) and 20-22 (Governing Law, Class Action, General) survive termination
Data Portability
You can create an encrypted backup in the app and restore it with your recovery phrase. After you delete your Identity without a backup, 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 where appropriate
- Updating the "Effective Date" at the top of this document
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.
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 are published on our website 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 |