Modify folder structure

mobile/traque-app/src/hook/useTimeDifference.jsx

@@ -0,0 +1,22 @@
+// React
+import { useEffect, useState } from "react";
+
+export const useTimeDifference = (refTime, timeout) => {
+    // If refTime is in the past, time will be positive
+    // If refTime is in the future, time will be negative
+    // The time is updated every timeout milliseconds
+    const [time, setTime] = useState(0);
+
+    useEffect(() => {
+        const updateTime = () => {
+            setTime(Math.floor((Date.now() - refTime) / 1000));
+        };
+
+        updateTime();
+        const interval = setInterval(updateTime, timeout);
+    
+        return () => clearInterval(interval);
+    }, [refTime, timeout]);
+
+    return [time];
+};