> For the complete documentation index, see [llms.txt](https://docs.vida.id/identity-stack/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vida.id/identity-stack/authentication/authentication-factors/cryptographic-token-pki/integration-methods/sdk.md).

# SDK

The **VIDA Phone Token SDK** empowers mobile and cross-platform applications with secure, cryptographic transaction signing and device-bound authentication. It supports **iOS**, **Android**, and **React Native**, enabling seamless integration into native and hybrid apps.

With built-in support for **asymmetric key generation**, **device-based key storage**, and **digital signature creation**, the SDK ensures that only registered, verified devices can sign and authorise sensitive operations, protecting your platform from tampering, spoofing, and unauthorised access.