Tracker Web API consists of 3 endpoints that have full CRUD (create, read, update, delete) support. The 3 endpoints are /api/trackedEntityInstances /api/enrollments and /api/events and they are responsible for Tracked entity instance, Enrollment and Event items.
http://your-server/api/trackedEntityInstances

{
    "trackedEntityType": "nEenWmSyUEp",
    "orgUnit": "DiszpKrYNg8",
    "attributes": [
      {
        "attribute": "w75KJ2mc4zz",
        "value": "Joe"
      }
    ],
    "enrollments":[
      {
         "orgUnit":"DiszpKrYNg8",
         "program":"ur1Edk5Oe2n",
         "enrollmentDate":"2017-09-15",
         "incidentDate":"2017-09-15",
         "events":[
            {
               "program":"ur1Edk5Oe2n",
               "orgUnit":"DiszpKrYNg8",
               "eventDate":"2017-10-17",
               "status":"COMPLETED",
               "storedBy":"admin",
               "programStage":"EPEcjy3FWmI",
               "coordinate":{
                  "latitude":"59.8",
                  "longitude":"10.9"
               },
               "dataValues":[
                  {
                     "dataElement":"qrur9Dvnyt5",
                     "value":"22"
                  }
               ]
            }
            
         ]
      }
   ]
}
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