External Links tile (not available by default) provides the ability to define external URLs ( to e.g. other data dashboards) in a tile:

Configuration

Example

{
  "type": "ExternalLink",
  "parameters": {
    "title": "Know more about CAST",
    "url":"http://www.castsoftware.com"
  },
  "color": "magenta",
  "col": 5,
  "row": 3,
  "sizex": 1,
  "sizey": 1,
  "min-sizex": 1,
  "min-sizey": 1,
  "max-sizex": 2,
  "max-sizey": 1
}