# Remote Digital Signature on Mobile Devices

## 1. Mobile Application Overview

SignCloud offers a cross-platform mobile application supporting:

- Android
- iOS


The mobile app allows users to securely approve signatures on the go.

## 2. Web Application Signing Scenario

SignCloud functionalities, as mentioned earlier, can also be accessed using a cross platform mobile app. Namirial
has develop a mobile app allowing remote digital signatures on any smartphone or tablet. A common use
case scenario considers an End-User who accesses a Web Application and needs to sing a document. The End
User is already authenticated to the Web Application (in the case shown in the example below it is an Internet
banking website, but it is apparent that this is valid for any type of Web Application) and the remote signature
process flow can be summarized in the following steps:

1. The Web Application produces a document to be digitally signed by the End User;
2. The Web Application requires the End User to sign the document;
3. The End User accepts to sign the document;
4. The Web Application, by means of a Service Platform sends a push notification to the End User
Device;
5. The End User clicks on the notification;
6. The Client App is started to manage the digital signature request;
7. The UKC Client App presents the document to be signed to the End User who can review the
document before deciding;
8. The End User selects the available Secure Element on the Cloud (remote smart card on HSM) in order
to make certificates available for the application;
9. The End User selects the appropriate certificate for digital signature;
10. The End User inserts the PIN number (or another Authenticator);
11. The signed document is returned to the Web Application that verifies and stores the digitally signed
document.


Another common use case is that the End User receives a document to be signed by email. By opening the
attached document with the SignCloud mobile client App, the End User can review the content of the
document ad digitally sign it according to the required format.

Remote Signing Process with the SignCloud mobile application
## 3. Email-Based Signing Scenario

User receives document via email.

1. Opens attachment using SignCloud mobile app.
2. Reviews content.
3. Selects certificate.
4. Authenticates.
5. Signs document.
6. Shares signed document.


## 4. Security Characteristics

- Secure HTTPS communication
- Remote key custody in HSM
- No private key stored on device
- Multi-factor authentication support


## 5. Advantages

- Full mobility
- Real-time push notifications
- Consistent security with desktop version