Privacy

Last updated 22 July 2026

The short version

Efflow stores what you put into it so it can show it back to you. It is a single-user app: nothing you write is visible to another account, and none of it is sold, rented or used for advertising.

What is stored

• Account — your name, email address, and either a password hash or the fact that you signed in with Google or Microsoft.
• Your content — events, tasks, notes, timers, calendars and the preferences that go with them.
• Connected calendars (optional) — if you connect Google, Outlook or iCloud, the access tokens for that connection and a read-only mirror of the events it returns. An Apple app-specific password is encrypted at rest.
• Billing — a Polar customer id and the status and dates of your subscription. Card numbers are never sent to or stored by Efflow; Polar handles the payment itself.

Who it is shared with

• Polar — merchant of record: payments, subscription management, invoicing and sales tax. Polar is the seller of record for Pro, so it collects the billing details a purchase requires and is the data controller for them.
• Neon (database) and Vercel (hosting) — where the app and its data run.
• Resend — sends account emails such as verification and password resets.
• Google / Microsoft / Apple — only if you connect a calendar, and only for that connection. Creating a meeting sends the event and its guest list to that provider, which then emails the invitations.
• Anthropic — only if the optional day-plan polish runs. It sends the titles and times of the suggested blocks, never note bodies, event notes or guests.

The calendar feed

The subscribe URL under Settings is a secret link: anyone holding it can read your event titles and times. Event notes are stripped from the feed. You can revoke or regenerate the link at any time, which immediately invalidates the old one.

Keeping and deleting

Your data is kept until you delete it. Deleting your account from Settings → Account removes your content and cancels any live subscription; Polar keeps its own payment records for as long as its financial-record obligations require. To request a copy of your data, or deletion by hand, email support@efflow.app.

Cookies

Efflow sets one session cookie so you stay signed in. There is no analytics, no tracking and no third-party advertising cookie.

Contact

Privacy questions or requests: support@efflow.app. See also the terms of service.