The application identifier, if the popularity is application-specific.
{ "id": 0, "productId": 0, "applicationId": 0, "sourceId": 0, "categoryRank": 0, "categoryRankMax": 0, "totalRank": 0, "rating": 0, "updated": "2019-08-24T14:15:22Z", "updatedBy": 0, "value": 0 }