Convert Utilities to TypeScript

frontend/src/Utilities/browser.ts

@@ -0,0 +1,15 @@
+import MobileDetect from 'mobile-detect';
+
+const mobileDetect = new MobileDetect(window.navigator.userAgent);
+
+export function isMobile() {
+  return mobileDetect.mobile() != null;
+}
+
+export function isIOS() {
+  return mobileDetect.is('iOS');
+}
+
+export function isFirefox() {
+  return window.navigator.userAgent.toLowerCase().indexOf('firefox/') >= 0;
+}