# SDKs

## Server-side SDKs

Server-side SDKs make it easy for you to use Twilio's REST APIs, generate TwiML, and perform other common server-side programming tasks. These SDKs are available in a variety of popular programming languages.

* [C# / .NET](https://github.com/twilio/twilio-csharp)
* [Java](https://github.com/twilio/twilio-java)
* [Node.js](https://github.com/twilio/twilio-node)
* [PHP](https://github.com/twilio/twilio-php)
* [Python](https://github.com/twilio/twilio-python)
* [Ruby](https://github.com/twilio/twilio-ruby)
* [Go](https://github.com/twilio/twilio-go)

## OpenAPI Specification

Twilio's OpenAPI specification empowers you with a broad set of developer tooling, ranging from Postman collections to API mocking to automatic client generation in over 40 programming languages.

* [Twilio OpenAPI Specification](https://github.com/twilio/twilio-oai)
* [Postman Collections](/docs/openapi/using-twilio-postman-collections/)
* [Mock API Generation](/docs/openapi/mock-api-generation-with-twilio-openapi-spec/)
* [Rust Client Generation](/docs/openapi/generating-a-rust-client-for-twilios-api/)

## JavaScript SDKs

Twilio's JavaScript SDKs are used in the browser to create video conversations, make VoIP phone calls, or implement real-time omnichannel chat. Get started with the SDK you need.

* [Voice](/docs/voice/sdks/javascript/)
* [Conversations](/docs/conversations/javascript/changelog/)
* [Video](/docs/video/javascript/)
* [TaskRouter](/docs/taskrouter/js-sdk/)
* [Sync](/docs/sync/javascript/changelog/)

## iOS SDKs

Our iOS SDKs enable native apps to create video conversations, make VoIP phone calls, and embed real-time omnichannel chat. Get started with the SDK you need.

* [Voice](/docs/voice/sdks/ios/)
* [Conversations](/docs/conversations/ios/changelog/)
* [Video](/docs/video/ios/)
* [Sync](/docs/sync/ios/changelog/)

## Android SDKs

Android SDKs enable you to create video conversations, make phone calls, and embed real-time omnichannel chat in your native Android apps. Get started with the SDK you need.

* [Voice](/docs/voice/sdks/android/)
* [Conversations](/docs/conversations/android/changelog/)
* [Video](/docs/video/android/)
* [Sync](/docs/sync/quickstart/android/)

## React Native SDK

Twilio's Voice SDK for React Native allows you to add voice-over-IP (VoIP) calling into your React Native apps.

* [Voice](/docs/voice/sdks/react-native)

## Flex SDKs

The Flex SDKs allow you to change the look, feel, and functionality of your Flex Contact Center using Javascript and React.

* [The Flex UI](/docs/flex/developer/ui/)
* [Installing and using Flex WebChat](/docs/flex/developer/messaging/webchat/setup/)