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. As tag you can use both, "sapui5" and "openui5". Or join the crowded discussion forum in the SAP Community Network (SCN). You can also get an invite to the unofficial OpenUI5 Slack channel created by the community.