Sub-processors
Last updated: October 4, 2026
Invoice Link uses the sub-processors below to deliver the Service. This list is published to satisfy §4 of our Data Processing Addendum. By accepting our Terms of Service, you authorize us to engage these sub-processors on your behalf.
We will provide at least 30 days' notice of any new sub-processor we engage (via email to the primary contact on your account or a notice on this page). If you object, you may terminate your subscription for convenience before the change takes effect.
| Sub-processor | Purpose | Data categories | Location | Privacy policy |
|---|---|---|---|---|
| Stripe, Inc. | Payment processing, Connect payouts | Payment tokens, transaction metadata, card last-4 | United States | View |
| PayPal, Inc. | PayPal payments and partner payouts — only on accounts where PayPal checkout is enabled | Payment tokens, transaction metadata | United States | View |
| Apple Inc. | App Store subscription billing, Sign in with Apple (if you choose it), push (APNs) | Subscription IDs, Apple sign-in identifier + email (or private relay email), push tokens | United States | View |
| Google LLC | Play Billing, Google Sign-In (if you choose it), address autocomplete (Maps Places API), Street View Static API, maps in the Android app (Maps SDK), push (FCM) | Subscription IDs, Google sign-in identifier + email, customer addresses, push tokens | United States | View |
| Google LLC (Google Cloud Document AI) | Receipt scanning (OCR) — used only after the user allows AI features | Receipt photos you scan and the text read from them (merchant, date, line items, totals). Not used to train models. | United States | View |
| RevenueCat, Inc. | Mobile subscription entitlement management | Subscription IDs, entitlement status, pseudonymous user ID | United States | View |
| Postmark (ActiveCampaign / Wildbit) | Transactional email delivery (invoices, reminders, receipts) | Recipient email, email content, delivery metadata, and whether an email was opened or a link clicked | United States | View |
| Railway Corp. | Backend API + database hosting | All service data at rest + in transit | United States | View |
| Vercel Inc. | Marketing site + invoice/receipt pages hosting, analytics | Request logs, IP addresses | United States | View |
| Expo (650 Industries, Inc.) | Push notification relay (via APNs/FCM), over-the-air updates | Push tokens, device identifiers, app version | United States | View |
| OpenAI, L.L.C. | AI features — AI assistant, Improve with AI, expense and receipt descriptions, file import (CSV/spreadsheet + image recognition), and moderation of assistant requests. Used only after the user allows AI features. | What you type or say to the assistant; recent chat context (can include client names, emails, phone numbers, invoice numbers, and amounts); saved item names + prices; notes text you ask AI to improve; draft expense notes + the store (vendor) name; draft payment-receipt descriptions + business trade; sample rows from imported files; images you import (e.g., invoices, contact lists, business cards). Not used to train models; may be retained up to 30 days for abuse monitoring. | United States | View |
| Cloudflare, Inc. (R2) | File storage | Invoice/estimate attachments, photos, receipt images, business logos | United States | View |
| Rentcast (Realty Data LLC) | Property data for addresses you look up, and the nearby-house search (Find Houses) in Door Knocker | Property addresses and, for Find Houses, the coordinates of where you are (no name, email, or account information) | United States | View |
| Functional Software, Inc. (Sentry) | Crash + error reporting (mobile + server) | Stack traces, device + OS info, route paths, a short technical trail of recent app activity, and your account ID + email (so we can follow up on a bug). Reports are filtered to strip invoice content and your customers' details before sending; the technical trail can occasionally still include a fragment of what you were doing, such as an address you were looking up. | United States | View |
| Better Stack (Logtail) | Server log aggregation | Operational logs + request metadata. PII (emails, names, payment IDs) redacted by the log shipper before transmission. | European Union (Frankfurt) — see DPA §5 | View |
Infrastructure sub-processors
Our primary sub-processors (Railway, Vercel) in turn rely on Amazon Web Services (AWS) and Cloudflare for underlying compute, storage, and edge delivery. These are fourth-level relationships we don't directly contract with but are listed here for transparency.
Questions
Email sentinelholdingsinc@gmail.com with any questions about our sub-processors or to request a copy of our DPA.