Subprocessors
Providers that support SuperMailbox and text processing used when semantic mail search is enabled.
Provider disclosures updated October 16, 2026.
| Provider | Purpose and processing location | Information involved | Current status |
|---|---|---|---|
| Google Gemini API | Text embedding when accumulated semantic mail search is enabled. Google says paid Gemini prompts and responses may be stored transiently or cached in any country where Google or its agents maintain facilities. See Gemini API Additional Terms. | If enabled: message subject and plain text loaded by SuperMailbox, including text prefetched from unread Inbox messages before you open them, plus the text of semantic-search queries. No attachments or images are sent for embeddings. | Used only when semantic mail search is enabled. |
| Yandex Cloud | BareMetal application compute, private MongoDB and OpenSearch, Lockbox secrets, container registry, monitoring infrastructure, and encrypted database backups. Primary region: ru-central1, Russia. | Account and mailbox metadata, encrypted mailbox credentials, billing and authorization records, cached message summaries and already-loaded message content, text search vectors, service logs and metrics, and encrypted database backups. | Configured and operating for the single SuperMailbox deployment. |
| Apple iCloud Mail | SMTP delivery of one-time SuperMailbox sign-in links. | Recipient email address, the sign-in email and one-time link, and delivery metadata. | Used to deliver SuperMailbox sign-in links through the configured SMTP service. |
| Hetzner | Shared WireGuard network gateway in Helsinki, Finland, used to route outbound IMAP and SMTP connections. | Network connection metadata needed to route mail traffic. The mail connection remains encrypted between SuperMailbox and the selected mail provider. | Gateway admission and routing configured for SuperMailbox. |
| Cloudflare | Authoritative DNS for supermailbox.app. | DNS zone records and DNS query metadata. | DNS only. Cloudflare's web proxy and cache are not enabled for the application records. |
| Stripe | Subscription checkout, billing management, and payment processing. | Customer and subscription identifiers and billing state. Stripe handles payment card details; SuperMailbox does not store full card numbers. | Live subscription billing is enabled for SuperMailbox. Stripe Checkout displays the selected plan, trial, and renewal terms before a customer confirms. |
| PostHog | Optional product usage analytics. The default capture endpoint is PostHog’s US service. | Opaque account ID, event name, product and surface, and limited event properties such as page view, mailbox provider, plan, or MCP tool name. Email content and addresses, message identifiers, search terms, mailbox names, OAuth secrets, and MCP arguments are excluded. | Events are sent only when the server project token is configured; users can opt out in Account settings. |
Mailbox providers and AI apps
When you connect a mailbox, the provider you choose receives the connection requests needed to carry out your instructions. It acts under its own terms and privacy practices. This user-selected provider relationship is separate from Apple iCloud Mail's use to send SuperMailbox sign-in links.
An AI app you authorize receives the email information returned by the tools you ask it to use. AI apps are selected by you and are not engaged by HARD TAB LLC as subprocessors for this service.
Google Gemini API is a separate service processor for SuperMailbox semantic search; it is not the same as connecting Gmail and is not the AI app you authorize. When semantic search is enabled, the Gemini terms above describe Google's handling of prompts and responses.
Changes
We will update this list when a provider or its role materially changes. The Privacy Policy describes the information involved and current data locations.