the fine print

Terms of Service

Last updated: 2026-04-27

Summary: use Flowblock to create drawings inside your own Notion workspace. Payments for Pro are handled by Polar.sh as Merchant of Record - their terms govern the purchase relationship. You can cancel your Pro subscription at any time. German law applies.

1. Who we are

Flowblock (the "Service") is operated by Alexander Kagoshima, based in Germany. Contact: [email protected]. Full legal details are in our Impressum.

2. The Service

Flowblock is a Chrome extension that lets you create and edit Excalidraw drawings and save them as image blocks inside your Notion workspace. The Service comprises the browser extension, the companion website at flowblock.app, and supporting backend infrastructure hosted on Cloudflare.

A free tier is available without a subscription and includes up to five drawings per calendar month. Additional features and unlimited usage require a paid Pro subscription.

3. Accounts and eligibility

To use Flowblock you must connect a Notion workspace via OAuth. You are responsible for keeping your Notion account credentials secure. You must be at least 16 years old to use the Service, or have the consent of a parent or legal guardian.

4. Acceptable use

You agree not to:

use the Service in a way that violates Notion's Terms of Service or API guidelines
attempt to bypass the free-tier quota, reverse-engineer license validation, or disrupt the backend
upload content that is unlawful, infringing, or harmful to others
use the Service to build a competing product by extracting its source code or behavior for that purpose

5. Paid subscriptions (Pro)

Pro subscriptions are sold and processed by Polar Software Inc. ("Polar"), acting as Merchant of Record. Polar handles payment processing, invoicing, VAT collection, and the statutory right of withdrawal (Widerrufsrecht). The purchase contract is concluded between you and Polar; we are the provider of the underlying Service.

Pricing and billing cycle are shown at checkout. The monthly plan is billed every two months in advance. The yearly plan is billed once per year. Prices include applicable taxes; your exact amount will be shown by Polar at checkout based on your country.

Right of withdrawal (Widerrufsrecht). As a consumer within the EU, you have a statutory 14-day right of withdrawal for digital subscriptions. Polar will display the Widerrufsbelehrung and a model withdrawal form at checkout. To exercise the right, follow the instructions provided by Polar in your purchase confirmation email.

Cancellation. You can cancel your Pro subscription at any time through the Polar customer portal (link sent in your purchase confirmation email). After cancellation, Pro features remain available until the end of the paid period; no further charges will be made.

6. Free tier changes

We may adjust the free-tier quota or Pro feature set in the future. Material changes will be announced at least 30 days in advance via the extension or by email. If you disagree with a change, you may stop using the Service; for Pro subscribers, cancellation at the next renewal is always available.

7. Availability and warranty

We aim for high availability but do not guarantee uninterrupted or error-free operation. Planned maintenance, third-party outages (Notion, Cloudflare, Polar), and changes to upstream APIs may temporarily affect the Service.

For paid Pro subscriptions, statutory warranty rights for digital products under §§ 327 ff. BGB apply in full and are not restricted by these Terms. The free tier is provided without consideration; we will nonetheless make reasonable efforts to maintain it.

8. Liability

We are liable without limitation for (a) intent and gross negligence, (b) injury to life, body, or health, (c) claims under the German Product Liability Act (Produkthaftungsgesetz), (d) any guarantee we have expressly assumed, and (e) liability under Art. 82 GDPR.

For breaches of material contractual obligations caused by simple negligence, our liability is limited to typical, foreseeable damages. Material contractual obligations are those whose fulfilment makes the proper performance of the contract possible in the first place and on whose observance the contract partner regularly relies (e.g. providing access to the Service for paying subscribers, processing save and upload requests without data corruption).

For data loss, our liability is additionally limited to the amount that would typically have been required to restore the data had the user maintained reasonable and regular backups. Users are responsible for keeping their own copies of important diagrams; the Service is not a backup or archival system.

To the extent liability for simple negligence is not already excluded above, our aggregate liability per contract year is limited to the fees paid by the user for the Service in the twelve months preceding the event giving rise to the claim. This cap does not apply to the cases of unlimited liability listed in the first paragraph and does not reduce statutory minimums for consumers.

Any further liability is excluded. These limits apply correspondingly to our employees, representatives, and vicarious agents (Erfüllungsgehilfen).

9. Termination

You can terminate use of the Service at any time by uninstalling the extension and disconnecting the integration from Notion. For paid subscriptions, see section 5. We may suspend or terminate access if you materially breach these Terms; we will notify you and, where feasible, give you an opportunity to cure.

10. Changes to these Terms

We may update these Terms to reflect changes in the Service, operational needs, or legal requirements. We will notify active users of material changes at least 30 days in advance. Continued use after the effective date constitutes acceptance.

11. Governing law and venue

These Terms are governed by the laws of the Federal Republic of Germany, excluding the UN Convention on Contracts for the International Sale of Goods. For consumers, this choice of law does not deprive you of the protection afforded by mandatory provisions of the law of your country of habitual residence. Venue is the competent court at our registered seat where legally permitted; consumer jurisdiction rules remain unaffected.

12. Severability

If any provision of these Terms is held invalid or unenforceable, the remaining provisions remain in full effect. The invalid provision shall be replaced by one that most closely reflects the economic purpose of the original.

13. Contact

Questions about these Terms: [email protected].