> For the complete documentation index, see [llms.txt](https://docs.tiun.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tiun.io/sdk/readme.md).

# Overview

tiun ships **two SDKs**. They do the same job — payments, subscriptions, and access control — but they are separate packages with separate APIs. Pick the one that matches what you're building.

|                | **Web SDK**                                                       | **React Native SDK**                                                             |
| -------------- | ----------------------------------------------------------------- | -------------------------------------------------------------------------------- |
| **Package**    | [`@tiun/sdk`](https://www.npmjs.com/package/@tiun/sdk)            | [`@tiun/react-native-sdk`](https://www.npmjs.com/package/@tiun/react-native-sdk) |
| **For**        | Any website or web app — React, Vue, Next.js, Nuxt, plain HTML/JS | React Native apps on iOS and Android                                             |
| **API**        | A global `tiun` object you call `init()` on                       | A `<TiunProvider>` and hooks                                                     |
| **Covers**     | Authentication, checkout, time-based billing                      | Authentication and checkout                                                      |
| **Start here** | [Web SDK / Installation](/sdk/web-sdk/installation.md)            | [React Native SDK / Installation](/sdk/react-native-sdk/installation.md)         |

{% hint style="warning" %}
**They are not layered — pick one.** The React Native SDK is a standalone package; it does not wrap or depend on `@tiun/sdk`. A React Native app never installs the web SDK, and the web SDK's `tiun.init()` API does not apply there.
{% endhint %}

***

## What the SDK does

Whichever one you use, it's there to:

* **Accept payments** — Open a checkout flow and let users purchase products or subscriptions.
* **Control access** — Gate content behind a paywall based on what the user has bought.
* **Manage user sessions** — Let users log in, log out, and stay signed in across visits.

Everything runs on the client. There's no server-side code required to get started, and no payment UI for you to build — checkout, login, and paywall overlays are all provided.

***

## Building a native app that isn't React Native?

If your app is a native shell (Swift, Kotlin) hosting your own web app in a WebView, the **web SDK** runs inside that WebView unchanged — see [Native apps with a WebView](/sdk/other-platforms/webview.md). First-class Swift, Kotlin, and Flutter SDKs are on the roadmap.


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