> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/android/digital-signature/digi-sig-tool.md).

# Using digital signature tool in Android

Sign documents with ease using the DigitalSignature tool in the Tools package. Learn how to enable certificate-based signatures and save signed documents securely. Perfect for PDF viewing and signing.

{% hint style="warning" %}
For Android, available in the full version of the library only. See [Apryse full or standard?](/xamarin/get-started/faq/full-vs-standard.md)
{% endhint %}

The Tools package comes with a basic [`DigitalSignature`](https://sdk.apryse.com/api/android/javadoc/reference/com/pdftron/pdf/tools/DigitalSignature.html) tool that allows signing with a specific keystore and password. The `DigitalSignature` tool can be used with the UI components such as [DocumentActivity](/android/open-save-document/open.md) and [PdfViewCtrlTabHostFragment2](/android/open-save-document/open.md). You can also use the tool with [PDFViewCtrl](/android/open-save-document/open/view.md) through [ToolManager](/android/ui-customization/set-tool-to-toolmanager.md).

![](https://226546913-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F0QItsdFBmuuL9ezHimHy%2Fuploads%2Fgit-blob-285fb3d877e22a706d94c5f900a1c1e65628d32b%2F15b1cabeb18061e135cdf37d1c41e2436e44cc3b-1080x2220.gif?alt=media)

By default, the signature tool does not sign with a certificate. Certificate-based signatures can be enabled using `ToolManagerBuilder` which will add a certificate picker and password input field to the signature UI flow.

Alternatively you can define a certificate file and password in `ToolManagerBuilder`. This will disable the additional signing flow for digital signatures and use the specified certificate instead.

{% tabs %}
{% tab title="Java" %}
{% code lineNumbers="true" %}

```java
ToolManagerBuilder tmBuilder = ToolManagerBuilder.from()
    .setUseDigitalSignature(true)
    // Optionally specify a default certificate file and password
    .setDigitalSignatureKeystorePath("my_keystore_path")
    .setDigitalSignatureKeystorePassword("my_keystore_password");
ViewerConfig.Builder builder = new ViewerConfig.Builder();
ViewerConfig config = builder
    //...
    .toolManagerBuilder(tmBuilder)
    .build();
```

{% endcode %}
{% endtab %}

{% tab title="Kotlin" %}
{% code lineNumbers="true" %}

```kotlin
val tmBuilder = ToolManagerBuilder.from()
  .setUseDigitalSignature(true)
  // Optionally specify a default certificate file and password
  .setDigitalSignatureKeystorePath("my_keystore_path")
  .setDigitalSignatureKeystorePassword("my_keystore_password")
val builder = ViewerConfig.Builder()
val config = builder
  //...
  .toolManagerBuilder(tmBuilder)
  .build()
```

{% endcode %}
{% endtab %}
{% endtabs %}

The signed document is then saved to a separate file.


---

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