var collectionFilter = ee.ImageCollection('LANDSAT/LC08/C01/T1_RT_TOA')
  .filterBounds(geometry)
  .filterMetadata('CLOUD_COVER','less_than',4)
  .map(app);
print(collectionFilter)

var app = function (image)
{
//indice de vegetação
var ndvi = image.normalizedDifference(['B5', 'B4']);
image=image.addBands (ndvi.rename('NDVI'));

  return image
}

Map.onClick(function(lonlat){
  var pixel = ee.Geometry.Point([lonlat.lon, lonlat.lat])
  var collection = collectionFilter
    .select(
      ["NDVI"]
    )
    var options = {
        title : 'NDVI CHART VALUES'
      };

    var graph = (
    ui.Chart.image.series(
      collection,
      pixel,
      ee.Reducer.mean(),
      30
    )
    .setOptions(options)
  );
      print(graph

  )

  Export.table.toDrive({
    collection: collection,
    description:  'exporting in json format each click',
    fileFormat: 'JSON'
  });

})