How do I create a widget?

You can use the SignStix webview tool in Creator along with SignStix javascript API to build components for SignStix. There are some examples here: https://bitbucket.org/signstix/code-snippets

The gist is that you create a webview layer with a URL of 'about:blank', then use the JS Extension to contain the 'widget'. There's some examples in the link above for Twitter feeds.

There's more information on the webview and the JS API in these pages:

https://www.signstix.com/support/how-do-i-use-a-web-view-in-a-sign/

https://cms.signstix.com/jsapi/