Guide
How to Add E-Signatures to Your App
Any app — mobile, web, or desktop — can add e-signatures via the Signbee API.
Steps
- 1
Get a free API key from signb.ee
- 2
Call POST /api/send with your document content
- 3
Signbee handles PDF generation, emails, and signing UX
- 4
Both parties receive the signed PDF
- 5
Works with iOS, Android, React Native, Flutter, and web
Try it with curl
curl -X POST https://signb.ee/api/send \
-H "Content-Type: application/json" \
-d '{
"content": "# Your Document\n\nContent here...",
"senderName": "Your Name",
"senderEmail": "you@email.com",
"recipientName": "Recipient",
"recipientEmail": "recipient@email.com"
}'Legal validity
Electronic signatures are legally binding under the ESIGN Act (US), eIDAS Regulation (EU), and Electronic Communications Act (UK). Every Signbee document includes a SHA-256 tamper-proof certificate.
More details
Adding e-signatures to your app doesn't require an SDK, native module, or heavy dependency. The REST API approach works with any language, framework, or platform.
Two integration patterns:
1. Redirect pattern (simpler): - Your backend sends the document via API - API returns a signing_url - Your app opens the signing_url in the system browser - User signs and is redirected back to your app - Best for: mobile apps, simple integrations
2. Embedded pattern (seamless): - Your backend sends the document via API - API returns a signing_url - Your app loads the signing_url in a WebView or iframe - User signs without leaving your app - Best for: web apps, apps requiring a seamless UX
Backend-only architecture: All API calls should be made from your server, not from the client. The API key should never be exposed in client-side code.
Webhook integration: Register a webhook URL to receive notifications when documents are signed. This lets your app react immediately — updating order status, triggering onboarding, or processing payments.
Frequently asked questions
Do I need a native SDK to add e-signatures?
No. The REST API works with any platform. Make HTTP POST requests from your backend, and embed the signing URL in a WebView or iframe on the frontend.
Can I embed the signing experience inside my app?
Yes. Use the signing_url returned by the API in a WebView (mobile) or iframe (web). The user signs without leaving your app.
Related resources
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