Letterbook Docs
Connect mobile apps with the API
Create support conversations from iOS, Android, or in-app help flows.
Last updated June 25, 2026
What this guide covers#
Use the API when mobile or in-app support requests should create Letterbook conversations.
Mobile support works best when the first ticket includes the context a support teammate would otherwise ask for: app version, device, account ID, active subscription, current screen, and error details.
Setup steps#
- Add a "contact support" or "report a problem" flow in the app.
- Send the form submission to your own backend.
- Validate the request and identify the authenticated customer.
- Add app, device, account, and error metadata.
- Call the Letterbook API from your server.
- Store the returned conversation ID if you want to link back from your app.
- Show the customer a clear confirmation or fallback if ticket creation fails.
Security note#
API keys belong on your server, not inside distributed mobile clients. Mobile apps can be reverse engineered, so anything embedded in the app should be treated as public.
Use your backend to:
- Authenticate the app user.
- Attach trusted user and account identifiers.
- Remove sensitive fields that should not enter support.
- Rate limit abusive submissions.
- Call Letterbook with the server-side API key.
Recommended metadata#
Include metadata that helps support resolve the issue faster:
- User ID and account ID
- Customer email and name
- App version and build number
- iOS or Android version
- Device model
- Current screen or feature
- Error code or failed request ID
- Subscription or entitlement state
Do not send passwords, tokens, full device logs, or sensitive customer data that support does not need.
Testing checklist#
Test:
- Authenticated user submission
- Logged-out or anonymous submission, if supported
- Network timeout and retry behavior
- Duplicate submission prevention
- Long messages and validation errors
- Links from your app or admin tools back to the Letterbook conversation