Integrate it by putting a thin “chat API” layer between your mobile app and your RAG provider: the app sends messages to your backend, your backend calls the RAG chat-completions endpoint, then streams or returns the response to the app with citations. This keeps API keys off devices and improves security and control.
In CustomGPT, you typically call the chat completions endpoint for your agent/project and session to get grounded answers from your indexed content.
For production mobile apps, avoid calling vendor APIs directly from the client—OWASP flags authentication/token handling as a major API risk area, and “key-in-app” patterns are easy to leak.
What does the minimum architecture look like?
A safe, standard setup:
- Mobile app (iOS/Android): UI + local state only
- Your backend: auth, rate limits, logging, prompt/guardrails
- CustomGPT API: retrieval + answer generation (grounded responses)
What should I send in each request?
Send:
- user_message
- session_id (conversation continuity)
- optional context: user_id, locale, app_version
- optional policy flags: “citations required”, “refuse if not found”
CustomGPT supports “send a message to a conversation” style chat-completions flows (project + session scoped).
Should my mobile app call CustomGPT directly, or through my backend?
Use your backend in almost all real deployments.
| Option | Pros | Cons | Best for |
|---|---|---|---|
| Direct-from-mobile → CustomGPT | Faster to prototype | API key exposure, less control | Demos / internal prototypes |
| Mobile → Your backend → CustomGPT | Secure keys, better governance, analytics, rate limiting | More engineering | Production apps |
Should I stream responses to mobile (typewriter effect), or return in one payload?
- Stream if you want faster perceived latency and chat UX
- Single response if you need simpler networking + caching
Either way, keep the “final answer + citations” structure consistent for trust and debugging.
(CustomGPT’s API is designed around conversation/message interactions; your backend can pass-through streaming if supported by your chosen HTTP stack.)
What security controls matter most for mobile + RAG?
Prioritize:
- No API keys in the client
- User auth + short-lived tokens
- Server-side rate limiting
- Request logging & redaction
- Permission-aware retrieval (only show what this user can access)
OWASP mobile/auth guidance emphasizes secure session handling and token lifecycle management (e.g., deleting tokens on logout, invalidating refresh tokens).
How do I implement this with CustomGPT specifically?
- Create/choose your CustomGPT agent and ensure your content is ingested and up to date.
- Generate an API key and store it only on your server.
- Backend endpoint: /chat
- validates your app user
- maps user → session_id
- calls CustomGPT chat completions endpoint (project + session)
- Return: answer, citations/sources, confidence (if you track it), and optional follow_ups.
If you want quicker integration, CustomGPT also publishes an SDK-focused approach to embed chatbot functionality into applications.
What’s a production-ready “API contract” for my mobile app?
Use a simple schema your UI can trust:
Request
- message: string
- sessionId: string
- context: { userId, orgId, locale }
Response
- answer: string
- sources: [{ title, snippet, url_or_doc_id }]
- followUps: string[]
- safety: { refused: boolean, reason?: string }
This makes it easy to render citations, handle “not found,” and avoid silent hallucinations.
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