How to use the bowser.ios function in bowser

function Tooltip(props: Props) {
  const tippyProps = props;

  // HACK: Emulate Android tooltip behavior (hold to show tooltip, tap to
  // activate click) on iOS
  if (tippyProps.touchHold && bowser.ios) {
    tippyProps.trigger = 'focus';
  }

  return ;
}

var browserQuirks = {

  // On most browsers we need to pad the tile edges with repeated pixels so
  // that the borders between neighboring tiles aren't apparent.
  // On iOS this isn't required, but we must disable it because the padding is
  // incorrectly rendered on top of the neighboring tile.
  padSize: browser.ios ? 0 : 3,

  // In order to prevent fallback tiles from overlapping their children, iOS
  // requires smaller zoom levels to be placed below larger zoom levels in
  // the CSS 3D coordinate space.
  reverseLevelDepth: browser.ios,

  // A null transform on the layer element is required so that transitions
  // between layers work on iOS.
  useNullTransform: browser.ios,

  // On Webkit and Gecko browsers, some tiles become invisible at certain
  // angles, usually non-floor tiles when looking straight down. Setting the
  // translateZ following the perspective transform to a slightly larger value
  // than the latter seems to work around this glitch.
  perspectiveNudge: browser.webkit || browser.gecko ? 0.001 : 0

};


/**
 * @class CssStage
 * @extends Stage
 * @classdesc
 *
 * A {@link Stage} implementation using CSS 3D Transforms.

componentDidMount() {
    if (this.props.registerHook) {
      this.normalizeHook = this.props.registerHook('preSubmit', input => {
        if (input.richTextBody) {
          return {
            ...input,
            richTextBody: htmlNormalizer(input.richTextBody),
          };
        }
      });
    }

    // Skip IOS due to a bug, see https://www.pivotaltracker.com/story/show/157434928
    if (this.props.isReply && !bowser.ios) {
      this.ref.focus();
    }
  }

let fn = evt => this.dispatchDOMEvent(evt, this.world, morphMethod);
      this.handlerFunctions.push({node: globalEmitter, type, fn, capturing});
      let arg = { capture: capturing, passive };
      globalEmitter.addEventListener(type, fn, arg);
    });

    this.keyInputHelper = new TextInput(this).install(rootNode);

    // rms 6.9.18: In order for us to handle touch events ourselves,
    //             we need to pass this undocumented touch-action attribute as "none"
    //             to the body of the document, since iOS does not support the
    //             CSS property touch-action.
    if (bowser.firefox) rootNode.setAttribute("touch-action", "none");
    // rms 3.9.19: Setting touch-action to none seems to break the scroll on iOS9 and possibly others.
    //             setting it to auto seems to fix things for now.
    if (bowser.ios) rootNode.setAttribute("touch-action", "auto");

    return this;
  }

// Add the stage element into the DOM.
  this._domElement.appendChild(this._stage.domElement());

  // Create control container.
  // Controls cannot be placed directly on the root DOM element because
  // Hammer.js will prevent click events from reaching the elements beneath.

  // The hotspot containers will be added inside the controls container.
  this._controlContainer = document.createElement('div');
  setAbsolute(this._controlContainer);
  setFullSize(this._controlContainer);

  // Prevent bounce scroll effect on iOS.
  // Applied only for iOS, as Android's events must have the default action to allow interaction with hotspots.
  if (browser.ios) {
    this._controlContainer.addEventListener('touchmove', function(event) {
      event.preventDefault();
    });
  }


  // Old IE does not detect mouse events on elements without background
  // Add a child element to the controls with full width, a background color
  // and opacity 0
  var controlCapture = document.createElement('div');
  setAbsolute(controlCapture);
  setFullSize(controlCapture);
  setBlocking(controlCapture);

  this._controlContainer.appendChild(controlCapture);
  domElement.appendChild(this._controlContainer);

<p>
            Thank you for helping us improve NUSMods. If you have left your email, we will send you
            a message when your update goes live
          </p>
        
      );
    }

    if (this.state.submitting) {
      return ;
    }

    // HACK: There's an iOS bug that clips the expanded map around the modal,
    // making it impossible to exit the expanded state. While we find a better
    // solution for now we'll just hide the button
    const showExpandMapBtn = !bowser.ios;

    return (
      <form>
        {this.state.error &amp;&amp; (
          <div>
            <div>
              There was a problem submitting your feedback. Please try again later.
            </div>
          </div>
        )}

        <div>
          <label>Email (optional)</label>
          </div></form>

it('cut should be supported on Firefox 41+', function() {
                assert.equal(document.queryCommandSupported('cut'), true);
            });
        }
        else {
            it('copy should not be supported on Firefox 40-', function() {
                assert.equal(document.queryCommandSupported('copy'), false);
            });

            it('cut should not be supported on Firefox 40-', function() {
                assert.equal(document.queryCommandSupported('cut'), false);
            });
        }
    }

    if (bowser.safari || bowser.ios) {
        it('copy should not be supported on Safari', function() {
            assert.equal(document.queryCommandSupported('copy'), false);
        });

        it('cut should not be supported on Safari', function() {
            assert.equal(document.queryCommandSupported('cut'), false);
        });
    }

    if (bowser.msie || bowser.msedge) {
        it('copy should be supported on IE', function() {
            assert.equal(document.queryCommandSupported('copy'), true);
        });

        it('cut should be supported on IE', function() {
            assert.equal(document.queryCommandSupported('cut'), true);

centerDialog = () => {
    let height = this.refs.dialog.offsetHeight / 2,
        width = this.refs.dialog.offsetWidth / 2,
        midPointY = window.innerHeight / 2 + window.pageYOffset,
        midPointX = window.innerWidth / 2 + window.pageXOffset;

    midPointY = midPointY - height;
    midPointX = midPointX - width;

    if (midPointY < 20) {
      midPointY = 20;
    } else if (Bowser.ios) {
      midPointY -= window.pageYOffset;
    }

    if (midPointX < 20) {
      midPointX = 20;
    }

    this.refs.dialog.style.top = midPointY + "px";
    this.refs.dialog.style.left = midPointX + "px";
  }

.then(({token}) => {
        if (!bowser.safari && !bowser.ios) {
          dispatch(handleAuthToken(token));
        }
        dispatch(hideSignInDialog());
      })
      .catch((error) => {