The 'Fully Deployed on the Tuya Server' mode is that all the code of SaaS is developed by Tuya, and deployed on Tuya server. The SaaS's host is provided by Tuya and developer could not add your private microapp into SaaS.
The 'Hybrid Deployment' mode is that part of code for a SaaS application is developed by yourself and deployed on your server. You can also define your host for the SaaS.
Detailed content, please refer to：View SaaS deployment method