How to set up and use an e-Signature

Welcome to the guide for using the e-Signature system within the AdBooks application. This module allows your clients to sign your invoices and estimate invoices directly online, securely and in a legally relevant manner, without printing, scanning, or exchanging emails.

—

🚀 How to enable e-Signature on an invoice or estimate? The e-Signature is enabled individually, for each invoice or estimate invoice separately, at the time of creation or editing.

1. Open the invoice/estimate creation or editing screen as usual.
2. Find the option Enable e-signature and check it.
3. Save the invoice/estimate as usual.

💡 Note: When the e-signature is enabled on a document, your client will see a signing button when opening the public link of the invoice/estimate.

—

📤 How does the client sign the document?
When you send the invoice/estimate to the client, the signing process looks like this:

1. The client opens the invoice/estimate link – no account or password is required.
2. The client reviews the document and clicks the signing button.

3. The system sends a one-time verification code (OTP) to the client’s email.

4. The client enters the code and then signs by hand – drawing their signature with a finger (on a phone/tablet) or a mouse (on a computer), directly on the screen.

5. Upon signing, the document is immediately locked, and the client receives confirmation that the signature has been successfully recorded.

⚠️ The client can also refuse to sign at any time instead of signing – this action is also logged.

—

🔒 What happens after signing?

• The invoice/estimate automatically gets the status Signed and a visual “Locked” label.

• The document can no longer be edited, deleted, or converted – this protects both you and the client from subsequent changes after the signature has been given.

• If the invoice was generated from a estimate as an advance or final invoice, a clear banner is displayed at the top of the document highlighting this.

—

📜 Audit Trail – complete transparency

Every action on the document is recorded:

• When the link was generated and sent

• When the client first opened/viewed the document

• When the verification code was sent and verified

• Exact time, IP address, and device from which the document was signed

• If the document was refused – when and (optionally) why

—

⚠️ Troubleshooting

The client is not receiving the verification code (OTP)?

• Check if the client has a correctly entered email in their profile.

• The code has a limited lifespan – if it expires, the client can request a new code. The document cannot be edited?

Dokument se ne može uređivati?

This is expected behavior after a document is signed – signed documents are permanently locked for legal security. If a change is truly necessary, create a new document (e.g., a new invoice).

I don’t see the e-signature option on the invoice?

Check if you enabled the “Enable e-signature” option while creating/editing that specific document – the function is enabled individually per document, not globally.