--- title: "Nutrient 4.4 migration guide" canonical_url: "https://www.nutrient.io/guides/android/migration-guides/pspdfkit-4-4-migration-guide/" md_url: "https://www.nutrient.io/guides/android/migration-guides/pspdfkit-4-4-migration-guide.md" last_updated: "2026-05-21T11:22:21.505Z" description: "Migration guide for Nutrient Android SDK version 4.4 with breaking changes, API updates, and upgrade instructions." --- This article provides a set of guidelines for migrating from version 4.3 to version 4.4 of Nutrient Android SDK. If you’re upgrading from a version earlier than 4.0, review the [Android 4 migration guide](https://www.nutrient.io/guides/android/migration-guides/pspdfkit-4-migration-guide.md) first. ## Digital signatures The digital signing framework, which we [introduced in Nutrient Android SDK 4](https://www.nutrient.io/guides/android/changelog.md#4.0.0), was partially rewritten to support external signature providers such as hardware security modules (HSMs) and other signing entities. Moreover, the signing APIs were extended to support the implementation of multi-step signing flows — for example, when user interaction is required during the signing process. Several methods from the original digital signatures API have been deprecated. If your app uses a custom `Signer` subclass, we encourage you to migrate to the new interface. The following resources should help you while you’re migrating to the new signing APIs: - Our [digital signatures](https://www.nutrient.io/guides/android/features/digital-signatures.md) guide - The `CustomSignatureProviderExample` in our Catalog app, which gives a quick introduction to the new digital signing APIs ## Deprecated Signing methods To fully support the newly added APIs, we deprecated the following methods on the `Signer` and `MemorySigner` classes: - `Signer` _ `signFormFieldAsync(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, java.io.OutputStream)` _ `signFormFieldAsync(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, com.pspdfkit.signatures.BiometricSignatureData, java.io.OutputStream)` _ `signFormField(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, java.io.OutputStream)` _ `signFormField(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, com.pspdfkit.signatures.BiometricSignatureData, java.io.OutputStream)` - `MemorySigner` _ `signFormFieldAsync()` _ `signFormField()` As a replacement, use the new `signFormField()` and `signFormFieldAsync()` methods on `Signer`. --- ## Related pages - [10 3 Migration Guide](/guides/android/migration-guides/10-3-migration-guide.md) - [10 4 Migration Guide](/guides/android/migration-guides/10-4-migration-guide.md) - [10 5 Migration Guide](/guides/android/migration-guides/10-5-migration-guide.md) - [2024 9 Migration Guide](/guides/android/migration-guides/2024-9-migration-guide.md) - [2024 8 Migration Guide](/guides/android/migration-guides/2024-8-migration-guide.md) - [Migrate to electronic signatures](/guides/android/migration-guides/migrating-to-electronic-signatures.md) - [Nutrient 10 Migration Guide](/guides/android/migration-guides/nutrient-10-migration-guide.md) - [Pspdfkit 2 1 Migration Guide](/guides/android/migration-guides/pspdfkit-2-1-migration-guide.md) - [Pspdfkit 2024 1 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-1-migration-guide.md) - [Pspdfkit 2024 4 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-4-migration-guide.md) - [Pspdfkit 2024 2 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-2-migration-guide.md) - [Pspdfkit 2024 3 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-3-migration-guide.md) - [Pspdfkit 2024 6 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-6-migration-guide.md) - [Pspdfkit 2024 7 Migration Guide](/guides/android/migration-guides/pspdfkit-2024-7-migration-guide.md) - [Pspdfkit 3 1 Migration Guide](/guides/android/migration-guides/pspdfkit-3-1-migration-guide.md) - [Pspdfkit 5 1 Migration Guide](/guides/android/migration-guides/pspdfkit-5-1-migration-guide.md) - [Migrate to Nutrient 3.0 with ease](/guides/android/migration-guides/pspdfkit-3-migration-guide.md) - [Pspdfkit 5 3 Migration Guide](/guides/android/migration-guides/pspdfkit-5-3-migration-guide.md) - [Pspdfkit 5 5 Migration Guide](/guides/android/migration-guides/pspdfkit-5-5-migration-guide.md) - [Pspdfkit 5 2 Migration Guide](/guides/android/migration-guides/pspdfkit-5-2-migration-guide.md) - [Migration guide for Android SDK 4 features](/guides/android/migration-guides/pspdfkit-4-migration-guide.md) - [Pspdfkit 6 2 Migration Guide](/guides/android/migration-guides/pspdfkit-6-2-migration-guide.md) - [Pspdfkit 6 3 Migration Guide](/guides/android/migration-guides/pspdfkit-6-3-migration-guide.md) - [Pspdfkit 6 1 Migration Guide](/guides/android/migration-guides/pspdfkit-6-1-migration-guide.md) - [Pspdfkit 6 6 Migration Guide](/guides/android/migration-guides/pspdfkit-6-6-migration-guide.md) - [Pspdfkit 5 Migration Guide](/guides/android/migration-guides/pspdfkit-5-migration-guide.md) - [Pspdfkit 6 4 Migration Guide](/guides/android/migration-guides/pspdfkit-6-4-migration-guide.md) - [Pspdfkit 7 Migration Guide](/guides/android/migration-guides/pspdfkit-7-migration-guide.md) - [Pspdfkit 8 7 Migration Guide](/guides/android/migration-guides/pspdfkit-8-7-migration-guide.md) - [Pspdfkit 8 6 Migration Guide](/guides/android/migration-guides/pspdfkit-8-6-migration-guide.md) - [Pspdfkit 8 9 Migration Guide](/guides/android/migration-guides/pspdfkit-8-9-migration-guide.md) - [Pspdfkit 6 Migration Guide](/guides/android/migration-guides/pspdfkit-6-migration-guide.md) - [Pspdfkit 8 8 Migration Guide](/guides/android/migration-guides/pspdfkit-8-8-migration-guide.md) - [Pspdfkit 8 Migration Guide](/guides/android/migration-guides/pspdfkit-8-migration-guide.md) - [Upgrading](/guides/android/advanced-integration/upgrading.md)