What is it?
It’s FREE. Download the latest stable UI5 Runtime, the UI5 SDK containing all documentation, or go to the download page for more options. Or even use OpenUI5 without downloading it at all, by using our CDN.
Try the Hello World, read the Developer Guide and refer to the API Reference. Check out stackoverflow.com to discuss code-related problems and questions. The OpenUI5 team will check regularly here for questions tagged with "sapui5". Or join the discussion in SAP Community Network (SCN).