json_schema: {
      "additionalProperties": false,
      "description": "Schema for a context that represents information pertaining to the current screen being viewed when an event occurs.",
      "minProperties": 2,
      "properties": {
          "activity": {
              "description": "Android specific: name of activity.",
              "type": "string"
          },
          "fragment": {
              "description": "Android specific: name of fragment.",
              "type": "string"
          },
          "id": {
              "_format": "uuid",
              "description": "An ID from the associated screenview event.",
              "maxLength": 36,
              "type": "string"
          },
          "name": {
              "description": "The name of the screen viewed.",
              "type": "string"
          },
          "topViewController": {
              "description": "iOS specific: class name of the top level view controller.",
              "type": "string"
          },
          "type": {
              "description": "The type of screen that was viewed e.g feed / carousel.",
              "type": "string"
          },
          "viewController": {
              "description": "iOS specific: class name of the view controller.",
              "type": "string"
          }
      },
      "required": [
          "name",
          "id"
      ],
      "self": {
          "format": "jsonschema",
          "name": "screen",
          "vendor": "com.snowplowanalytics.mobile",
          "version": "1-0-0"
      },
      "type": "object"
  }