Terms of Service

1Who we are & agreement scope

These Terms cover the Engine Mail macOS app, the website at enginemail.io, our API, our secure-share pages, and related services. By creating an account, downloading or using an Engine Mail application, or using any part of the Service, you agree to these Terms. If you do not agree, do not use the Service. If you use the Service on behalf of an organization, you confirm you are authorized to accept these Terms for it. For the full registered name and address of the contracting entity, contact [email protected].

2Eligibility & authority

You must be at least 16 to use Engine Mail. If you are under the age of legal majority where you live, your parent or legal guardian must review and agree to these Terms and is responsible for your use of the Service. You may not use the Service if applicable law prohibits us from providing it to you.

3Your account & account security

You sign in with your email and a one-time code. Keep your account details accurate, use one account per person unless a team arrangement says otherwise, and do not share your account or sign-in codes. You are responsible for activity under your account. Tell us promptly if you suspect unauthorized use. You can revoke devices and sessions in the app. Account recovery depends on access to your verified sign-in address and any two-factor methods you configured; we are not required to bypass security controls when ownership cannot be verified.

4Software license & App Store terms

We grant you a personal, non-exclusive, non-transferable, revocable license to use Engine Mail on Apple-branded devices you own or control, for personal or internal business use. You may not copy proprietary code, reverse-engineer except where the law expressly allows, circumvent access controls, resell the Service, or use non-public interfaces without authorization. Open-source components are governed by their own licenses.

If you obtain Engine Mail through an Apple App Store, Apple's Standard Licensed Application End User License Agreement applies to your license to the application unless a custom license is presented at download. These Terms govern your Engine Mail account and use of the Service; if there is a conflict about the application license, the applicable App Store EULA controls for that issue. Apple is not responsible for the app or its content, has no support or warranty obligation for it, and Apple and its subsidiaries are third-party beneficiaries of these Terms with the right to enforce the app-license terms against you.

5Connected email accounts

Engine Mail connects to your mailboxes (Gmail, Outlook, iCloud, Yahoo, or a custom IMAP/SMTP server) on your behalf. You are responsible for having the right to access every mailbox you connect and for complying with each provider's terms. Your access tokens and app passwords are stored on your device; see the Privacy Policy for how push and sync work.

6Your Content & limited operational license

As between you and Engine Mail, you retain any rights you have in the email accounts, messages, contacts, drafts, files, comments, and other material you access, create, or provide through the Service ("Your Content"). These Terms do not give us ownership of Your Content. You are responsible for ensuring you have the rights, permissions, and lawful authority to connect each account and to use, process, share, or instruct us to process Your Content.

You grant us a non-exclusive, worldwide, royalty-free license to host, reproduce, transmit, format, sanitize, and display Your Content only as necessary to provide, secure, maintain, and support the features you choose to use (for example, Secure Email Share, Team Workspace, or support requests). We may allow our contracted service providers to process Your Content only for those purposes under appropriate restrictions. This license ends when the relevant content is deleted from our systems, subject to limited backup retention, legal obligations, and the Privacy Policy.

7Acceptable use

Don't use Engine Mail to:

• Send spam or unsolicited bulk messages, use deceptive sender or subject information, distribute malware or phishing, or evade your provider's sending limits.
• Access mailboxes, data, or shared content you are not authorized to.
• Break the law, or infringe or violate any third party's rights or terms (including your email provider's).
• Disrupt, overload, or attempt to circumvent the Service's security or limits.

Good-faith security research carried out in line with our vulnerability-disclosure process (contact [email protected]) is authorized and is not a violation of these Terms.

8AI features & Privacy Scrub

AI features are optional. They run on your device or, if you connect your own API key, through that provider under your key. AI output can be inaccurate; you must review it before you rely on, send, or act on it, and you should not use it as the sole basis for legal, medical, financial, employment, credit, housing, insurance, or other high-impact decisions. Cloud providers and external clients have their own terms, and any API charges or rate limits for bring-your-own-key providers are your responsibility. Engine Mail does not use Your Content to train Engine Mail's own models, but we cannot promise that a third-party provider you choose will never retain or train on data; that depends on your provider, account type, and its terms. The Privacy Scrub reduces exposure before cloud requests but cannot guarantee removal of every identifier.

9MCP & external clients

MCP is optional and off by default. If you connect an external client through MCP, you authorize Engine Mail to make the accounts and capabilities selected for that key available to the client. Requests made with a valid key are treated as authorized instructions until the key is revoked, subject to the app's approval controls. The client may process or transmit authorized data under its own terms and privacy policy, which we do not control. You are responsible for choosing a trusted client, limiting its permissions, protecting and rotating its key, reviewing requested actions (including recipients and content before a send), and revoking access when it is no longer needed.

10Automations, security tools & permanent actions

Features such as Auto Clean, cleaning rules, unsubscribe actions, block rules, scheduled sending, filters, and permanent delete can move, modify, send, or delete mail. Rules and AI suggestions can be inaccurate, so preview results and rule scope before enabling them. Some provider-side actions sync to all your devices, permanent deletion may not be recoverable, and scheduled messages can be delayed by connectivity or provider restrictions. We cannot guarantee delivery, receipt, or a successful unsubscribe. You remain responsible for the automated messages and actions you configure.

Security and privacy features (phishing checks, authentication checks, link analysis, spam and malware scanning, tracker blocking) provide signals and protective controls, not a guarantee that a message, sender, link, attachment, or website is safe. Threat intelligence can be incomplete or outdated, and legitimate content can be misclassified. Use reasonable judgment and do not rely on Engine Mail as your only security control.

11Email sending & tracking

You are responsible for the messages and tracking you configure through Engine Mail. You must comply with applicable privacy, electronic-communications, direct-marketing, and anti-spam laws (for example CAN-SPAM, CASL, and UK PECR), as well as your email provider's rules. You may not send unsolicited bulk messages, use deceptive sender or subject information, distribute malware, evade provider limits, or track recipients where notice, consent, or another lawful basis is required and has not been obtained. Outbound tracking can be turned off at any time; see the Privacy Policy for what tracking processes.

12Team Workspace

If you use Team Workspace, a person accepting for an organization confirms they are authorized to do so. Team owners or administrators may manage members, roles, shared threads, permissions, and organization data, and members must share only content they are authorized to share. Internal comments may be visible to authorized team members. Removing a member ends their future access but cannot recall content they already accessed, exported, or copied. Joining or administering a team does not give anyone control over another person's unrelated personal mailbox. Where an employer or organization provides the account, it may control that workspace.

13Secure Email Share

If you create a Secure Email Share link, you instruct us to host and display a sanitized copy of the selected content (and any attachments you separately choose to include) for people who receive the link. You must have the right and lawful authority to share that content, and you must not share confidential, personal, regulated, infringing, or unlawful material without appropriate authority. Anyone with the link (and the PIN, if you set one) may view it; a PIN and our automated protections reduce risk but do not guarantee confidentiality. You are responsible for choosing recipients and distributing the link securely. Links expire (at most 7 days) and can be revoked, but expiration and revocation cannot recall content a viewer already accessed, copied, or saved. We may remove or disable a link for abuse, legal, security, infringement, or Terms reasons. Report an abusive or unlawful share to [email protected].

14Third-party connected services & our service providers

Connected services that you choose, such as your email providers, cloud AI providers, and external MCP clients, are governed by their own terms, and their availability is outside our control. We are not responsible for those services.

Our service providers (hosting, transactional email, diagnostics, push, CDN, and security vendors we use to operate Engine Mail) act on our behalf, and we remain responsible for them to the extent required by law and our contracts.

15Plans, billing & cancellation

Engine Mail is currently offered at no charge. If we introduce paid plans, we will clearly show the price, billing interval, taxes, renewal, and cancellation terms before you are charged, and those terms will supplement these Terms. Where you purchase through an app store, that store's billing, cancellation, and refund rules also apply. We will give notice of a price change as required by law.

16Referrals & rewards

If a referral or rewards program is offered, a referral counts only after the stated qualifying event, and rewards have no cash value and are non-transferable. Self-referrals, fake accounts, purchased referrals, spam, automation, misleading promotion, and other manipulation are not allowed, and we may withhold, correct, or reverse rewards obtained that way. We will not remove legitimately earned rewards without cause, and we will give reasonable notice before materially changing or ending the program where feasible. Any taxes on rewards are your responsibility.

17Intellectual property, open source & feedback

The Engine Mail app, website, name, logo, and design are owned by us and protected by law; these Terms grant no rights beyond the license in section 4, and no implied license to our trademarks. Open-source components remain under their own licenses, and third-party names and logos belong to their owners. If you send us feedback or suggestions, we may use them without restriction or payment, and doing so does not give us ownership of your unrelated content.

18Service updates & availability

We work to keep the Service available and reliable, but email providers, networks, operating systems, and other dependencies can cause interruptions or delays. We do not guarantee that every feature will always be available, uninterrupted, or error-free. We may update the Service to improve functionality, security, compatibility, or legal compliance, and where reasonably possible we will give advance notice before discontinuing a material paid feature. Always keep your own copies of important mail with your provider.

19Suspension, termination & account deletion

You can stop using Engine Mail and delete your account at any time. We may suspend the Service immediately for an active security threat, fraud, illegal use, or an urgent legal obligation; for other material breaches, we will give reasonable notice and an opportunity to cure where practical, and a route to appeal. On termination your license ends. Server-side data is handled under the Privacy Policy, and where practical and lawful we will give you a reasonable opportunity to export data we control. We do not guarantee that on-device content remains accessible after termination, since access can depend on app state, keys, connected providers, or software availability. Terms that by their nature should survive (including accrued payment obligations, intellectual property, disclaimers, liability limits, and dispute terms) survive termination.

20Warranties & disclaimers

The Service is provided "as is" and "as available", without warranties of any kind, to the fullest extent permitted by law. We do not warrant that the Service will be uninterrupted, secure, error-free, or that it will detect every threat. Nothing in these Terms excludes or limits warranties or rights that cannot legally be excluded or limited, including non-waivable consumer rights.

21Limitation of liability

To the maximum extent permitted by law, Engine Mail will not be liable for indirect, incidental, special, exemplary, or consequential losses, or for loss of profits, revenue, goodwill, or business opportunity. Our total aggregate liability arising from the Service will not exceed the greater of: (a) the amount you paid us for the Service in the 12 months before the event giving rise to the claim; or (b) USD 100 (or the equivalent in your local currency).

These limitations do not apply where liability cannot legally be limited, including for fraud, fraudulent misrepresentation, willful misconduct, gross negligence, death or personal injury caused by negligence, or violation of mandatory consumer rights. Additional exclusions may apply under your local law.

22Governing law & disputes

These Terms are governed by the laws of the country in which Engine Mail is established, without regard to conflict-of-law rules, and disputes are subject to the courts of that place. This does not deprive you of the mandatory consumer protections, or the right to bring a claim in the courts, of your country of residence where the law that applies to you provides them. For the specific governing law and forum, contact [email protected].

23Changes to these Terms

We may update these Terms to reflect changes to the Service, the law, security, or our business. We will post the updated Terms and revise the date above, and for material changes we will give reasonable advance notice through the Service, by email, or another appropriate method. Material changes apply prospectively from their effective date; if you do not agree, you may stop using the Service and cancel any renewing plan before they take effect. Changes required urgently for security or legal compliance may take effect sooner.

24General

These Terms, together with the Privacy Policy and any plan or feature terms, are the entire agreement between you and us about the Service. If a provision is unenforceable, the rest remains in effect. Our failure to enforce a right is not a waiver of it. You may not assign these Terms without our consent; we may assign them to an affiliate or in connection with a merger, acquisition, or transfer of the business, with notice where required. Neither party is liable for delays caused by events beyond its reasonable control. Headings are for convenience only. If we provide a translated version and it conflicts with the English version, the English version controls unless local law requires otherwise. There are no third-party beneficiaries except Apple, as described in section 4.

25Contact

For legal notices and questions about these Terms, email [email protected]. For general help, email [email protected]. See also our Privacy Policy.