> For the complete documentation index, see [llms.txt](https://api.vietqr.vn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://api.vietqr.vn/en/vn/other-api-service.md).

# OTHER API SERVICE

We provide a variety of APIs to support business expansion and product diversification for our clients, including:

* **VietQR Refund APIs**
* **API Host to Device (MQTTs)**
* **Host To Client**
* **API Sound Box Cloud.**