code: function takePhoto () {
    let sizeFactor = 1;
    let imageType = IMAGE_TYPES.JPG;
    let imageCompression = 1;
  
    let config = {
      sizeFactor,
      imageType,
      imageCompression
    };
  
    let dataUri = cameraPhoto.getDataUri(config);
    imgElement.src = dataUri;
  }
docs: function called by the buttons.