Add touch backend for mobile devices

src/components/Widgets/SignupQuestionsWidget/SignupQuestionsWidget.tsx

@@ -1,6 +1,7 @@
 import React from "react";
 import { DndProvider } from "react-dnd";
 import { HTML5Backend } from "react-dnd-html5-backend";
+import { TouchBackend } from "react-dnd-touch-backend";
 import styled from "styled-components";
 import shortid from "shortid";
 import colors from "@theme/colors";
@@ -62,9 +63,20 @@ const SignupQuestionsWidget: React.FC<SignupQuestionsWidgetProps> = ({ value, on
 
   const questions: SignupFormQuestion[] = JSON.parse(value);
 
+  // simple way to check whether the device support touch (it doesn't check all fallback, it supports only modern browsers)
+  const isTouchDevice = () => {
+    if ("ontouchstart" in window) {
+      return true;
+    }
+    return false;
+  };
+
+  // Assigning backend based on touch support on the device
+  const backendForDND = isTouchDevice() ? TouchBackend : HTML5Backend;
+
   return (
     <Widget>
-      <DndProvider backend={HTML5Backend}>
+      <DndProvider backend={backendForDND}>
         <QuestionList
           questions={questions}
           onChange={onValueChange}