# QSH client API workflow The QSH-exposed APIs are called QSH client APIs for applications. The client applications interact with the QSH framework available on the low-power processor. The following figure shows the detailed breakdown and usage of the QSH client APIs: **Figure: QSH client API workflow** The following list describes the QSH client APIs: - `getSession()`: To interact with the QSH, the sensor application client must create an interface session by invoking the `getSession()` API. Successful creation of the interface session returns an `ISession*` object to the client. - `open()`, `close()`, `setCallback()`, and `sendRequest()`: The interface that `getSession()` API creates operates on a *once\_per\_session* basis. This interface allows the client application to use the QSH client APIs, such as `open()`, `close()`, `setCallback()`, and `sendRequest()`, until the session is explicitly deleted using the `close()` and `delete()` APIs. After the interface session establishes, the client application or the client code can open a sensor session by calling the `open()` API. Similar to `getSession()`, the `open()` API is also invoked on a *once\_per\_session* basis. The `setCallback()` and `sendRequest()` APIs are invoked once for a specified SUID. **Next steps** > > > [Develop applications using the QSH client APIs](https://docs.qualcomm.com/doc/80-80022-7/topic/develop_app.html#develop-app) Last Published: May 07, 2026 [Previous Topic Develop with client APIs](https://docs.qualcomm.com/bundle/publicresource/80-80022-7/topics/develop_client_apis.md) [Next Topic Develop applications using the QSH client APIs](https://docs.qualcomm.com/bundle/publicresource/80-80022-7/topics/develop_app.md)