> For the complete documentation index, see [llms.txt](https://docs.payments.thalescloud.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.payments.thalescloud.io/release-notes/sdk/september-2025/d1-sdk-4.1.1.md).

# D1 SDK 4.1.1

{% tabs %}
{% tab title="Android" %}

#### Supported Platforms & Processor Architectures <a href="#supported-platforms--processor-architectures" id="supported-platforms--processor-architectures"></a>

* Android 8.0.0 and later.
* Processor architectures: armeabi-v7a, arm64-v8a, x86, x86\_64.

#### General <a href="#bug-fixes" id="bug-fixes"></a>

**Improvements**

* Security enhancements for D1 SDK.

#### NFC Payment

**Bug Fixes**

* Default card setting during digitization
* Resolved the issue where the first digitized card in the D1 Pay wallet was not automatically set as the default payment method. The current digitization flow automatically sets the first card as the default, eliminating the need to manually call the `d1PayWallet.setDefaultPaymentDigitalCard()` API after digitization.
  {% endtab %}

{% tab title="iOS" %}

#### Supported Platforms & Processor Architectures <a href="#supported-platforms--processor-architectures" id="supported-platforms--processor-architectures"></a>

* iOS 15 and later.
* Processor architectures: arm64, x86\_64.

#### General <a href="#bug-fixes" id="bug-fixes"></a>

**Improvements**

* Security enhancements for D1 SDK.
  {% endtab %}
  {% endtabs %}


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