Terms of Service

Last updated: 14 September 2026

1. Who these terms are with

These terms govern use of the CalendAIr mobile app and related services at calendair.de (together, the “Service”).

The provider is CalendAIr H.I. UG (haftungsbeschränkt), Fährstraße 217, 40221 Düsseldorf, Germany, registered with the commercial register of the local court (Amtsgericht) of Düsseldorf under HRB 114309, represented by Frederik Holz and Judith Ingenbleek, email support@calendair.de (“CalendAIr”, “we”).

By creating an account or using the app, you agree to these terms. If you do not agree, do not use the Service.

The Privacy Policy describes how we process personal data.

Definitions. In these terms, Service means the CalendAIr app together with its servers and the website. A meeting is an appointment you create in CalendAIr and invite others to. A connected calendar is a calendar at Google, Microsoft or Apple whose use you have authorised. An invite code is the code that connects two accounts. Premium is the paid subscription.

2. The Service

CalendAIr helps you find times when you and people you invite are free, create meetings, and sync those meetings to connected Google, Outlook, or iCloud calendars. Availability depends on the calendars you connect and on the providers’ APIs.

Free and Premium. CalendAIr is free to use. The free tier includes a monthly quota of AI requests and a limited number of connected calendars and invitees per meeting, and it is financed by advertising. Premium lifts the request quota, raises those limits, and removes ads. The limits that apply are shown in the app, and we may adjust them for future periods with reasonable notice.

AI suggestions. CalendAIr uses an AI model to turn what you type (for example “friday afternoon next week”) into time windows. AI output can be wrong or incomplete. A suggestion is a proposal, not a booking: check the date, time, and participants before you confirm a meeting.

We may change, limit, or discontinue features, and we may set fair-use limits to keep the Service running. We do not guarantee uninterrupted availability.

CalendAIr is not a replacement for your calendar provider. Google, Microsoft, and Apple remain responsible for their own products.

3. Eligibility and account

You must be at least 16 years old.

You sign in with Google or Apple. You are responsible for that account and for activity under it. Provide accurate information. Do not share access in a way that lets others misuse the Service.

We may suspend or close accounts that breach these terms or that we reasonably believe are abusive, unlawful, or a security risk.

4. Calendar access

You choose whether to connect a calendar. Connection uses cloud APIs (OAuth for Google and Outlook; CalDAV for iCloud with an app-specific password). It does not use the phone’s system calendar permission.

You must have the right to connect the calendars you link (for example, you own the account or your organisation allows it).

Deleting a meeting in CalendAIr, disconnecting a calendar, or deleting your CalendAIr account does not cancel or delete events that were already created on Google, Outlook, or iCloud. Those copies stay in the provider calendar until you (or the organiser) remove them there. We only delete our own records in CalendAIr.

5. Your responsibilities

You agree to use the Service lawfully and not to:

• probe, overload, or misuse our systems or the calendar APIs;
• try to access other people’s calendars or accounts without permission;
• upload unlawful, harmful, or infringing content as meeting titles or descriptions;
• reverse engineer the Service except where mandatory law allows it.

You are responsible for the content of meetings you create (title, description, who you invite).

Inviting other people. Only invite people who are happy to be contacted by you through CalendAIr. A meeting's title and description are visible to everyone invited and are written into their calendars once they accept.

No sensitive details in titles. We store meeting titles and descriptions so we can display them and write them to calendars. Please do not put particularly sensitive information there – about health, religion, political opinions or sex life, whether your own or anyone else's. A neutral title is enough.

6. Subscriptions and payments

Some features require a paid subscription (“Premium”). Price, billing period, renewal, and any trial are shown in the App Store or Google Play before you buy. Subscriptions renew automatically until you cancel.

Payment is charged by Apple or Google, not by us directly. The purchase contract for the subscription is concluded with the respective store, and cancellation, refunds, tax invoices, and your statutory right of withdrawal follow that store’s terms. Manage or cancel the subscription in your Apple ID or Google Play account settings. Deleting your CalendAIr account does not cancel it.

If a store notifies us that a subscription lapsed or was refunded, we may remove Premium access.

Introductory Premium period. New accounts may receive a limited period of Premium features free of charge. It is granted voluntarily, ends automatically, does not renew, and does not create a claim to further free use. We may change it or stop offering it at any time for new accounts.

Advertising. The free tier shows advertising. Whether you see personalised ads depends on the consent you give in the app, which you can change at any time. Premium is ad-free.

7. Right of withdrawal

If you are a consumer, you have a statutory right of withdrawal for distance contracts.

The contract for Premium is concluded with the respective store, not with us. Apple or Google therefore inform you about the right of withdrawal and how it lapses for digital content before you buy, and that is also where you exercise it. Refunds are handled by the store.

The free use of CalendAIr costs nothing. You can end it at any time, without notice and without giving reasons, by deleting your account (see section 10).

8. Intellectual property

We and our licensors own the app, branding, and software. We grant you a limited, non-exclusive, revocable licence to use the app for its intended purpose.

You keep rights in content you create (for example meeting titles). You grant us a licence to host and process that content as needed to provide the Service, including writing it to connected calendars and showing it to people you invite.

9. Liability

We are liable without limitation for intent and gross negligence, and for injury to life, body, or health.

In cases of slight negligence we are liable only for breach of a duty that is essential to the performance of the contract (a duty whose fulfilment makes due performance possible and on which you may normally rely). In that case liability is limited to typical, foreseeable damage.

Otherwise we are not liable for slight negligence.

The above does not shift the burden of proof to your disadvantage, and it does not limit liability under the German Product Liability Act.

We are not liable for the availability or correctness of Google, Microsoft, or Apple calendars, or for double-bookings caused by calendars you did not connect, delayed provider APIs, or information you entered incorrectly.

10. Duration and termination

The contract for the free use of CalendAIr runs for an indefinite period. You can end it at any time by deleting your account in the app or via Delete your account. A paid subscription is separate and is cancelled in the store (see section 6).

We may terminate the free contract with 30 days notice, and we may terminate or suspend it immediately for good cause, in particular a serious or repeated breach of section 5. Statutory rights of termination remain unaffected.

11. Changes to these terms

We may change these terms where there is a valid reason, for example a change in the law, in case law, in the technical or economic conditions of the Service, or a new feature.

We will notify you of the change in text form (in the app or by email) at least six weeks before it takes effect, together with the changed provisions and the date they apply from. The change takes effect only if you agree, or if you do not object within that period; we will point out the meaning of your silence in the notice. If you object, we may terminate the contract with 30 days notice. If a change is only to your advantage or does not affect your rights and obligations (for example a new optional feature or an editorial correction), it takes effect without this procedure.

12. Apps obtained from the Apple App Store

If you downloaded CalendAIr from the Apple App Store, the following applies in addition:

• These terms are concluded between you and CalendAIr only, not with Apple. CalendAIr, not Apple, is solely responsible for the app and its content.
• Apple has no obligation to provide maintenance or support for the app.
• If the app fails to conform to any applicable warranty, you may notify Apple, and Apple will refund the purchase price of the app, if any. To the maximum extent permitted by law, Apple has no other warranty obligation with respect to the app. Your statutory rights against us are unaffected.
• CalendAIr, not Apple, is responsible for addressing any claim by you or a third party relating to the app, including product liability claims, claims that the app fails to meet a legal or regulatory requirement, and claims under consumer protection or similar legislation.
• If a third party claims that the app infringes their intellectual property rights, CalendAIr, not Apple, is responsible for the investigation, defence, settlement, and discharge of that claim.
• You confirm that you are not located in a country subject to a US Government embargo or designated as a “terrorist supporting” country, and that you are not on any US Government list of prohibited or restricted parties.
• Apple and its subsidiaries are third-party beneficiaries of these terms and, upon your acceptance, have the right to enforce them against you.

13. Governing law and dispute resolution

These terms are governed by the law of the Federal Republic of Germany, excluding conflict-of-law rules. If you use the Service as a consumer, mandatory protections of the country where you live still apply.

The contract language is German. An English version is for convenience; if they differ, the German version prevails for users in Germany.

We are neither obliged nor willing to take part in dispute resolution proceedings before a consumer arbitration board (§ 36 VSBG). You can of course always reach us at support@calendair.de.

14. Contact