diff --git a/apps.json b/apps.json
index c9322b12a..3cafdae78 100644
--- a/apps.json
+++ b/apps.json
@@ -1718,7 +1718,7 @@
     "id": "simpletimer",
     "name": "Timer",
     "icon": "app.png",
-    "version": "0.05",
+    "version": "0.06",
     "description": "Simple timer, useful when playing board games or cooking",
     "tags": "timer",
     "readme": "README.md",
diff --git a/apps/simpletimer/ChangeLog b/apps/simpletimer/ChangeLog
index e548d90fa..0a0d47126 100644
--- a/apps/simpletimer/ChangeLog
+++ b/apps/simpletimer/ChangeLog
@@ -3,3 +3,4 @@
 0.03: BTN2 to open launcher
 0.04: Remember last set time
 0.05: Fix buzz that doesn't stop (fix #521)
+0.06: Fix buzz error, remove '+' when timer running and add 'back' text (fix #577)
diff --git a/apps/simpletimer/app.js b/apps/simpletimer/app.js
index 75c118980..f6332a8b7 100644
--- a/apps/simpletimer/app.js
+++ b/apps/simpletimer/app.js
@@ -1,6 +1,6 @@
 let counter = 0;
 let setValue = 0;
-let counterInterval;
+let counterInterval, alarmInterval;
 let state;
 let saved = require("Storage").readJSON("simpletimer.json",true) || {};
 
@@ -19,7 +19,8 @@ function outOfTime() {
   g.drawString("Time UP!", 120, 50);
   counter = setValue;
   buzzAndBeep();
-  setInterval(() => {
+  if (alarmInterval) clearInterval(alarmInterval);
+  alarmInterval = setInterval(() => {
     g.clearRect(0, 70, 220, 160);
     setTimeout(draw, 200);
   }, 400);
@@ -55,7 +56,9 @@ function countDown() {
 }
 
 function clearIntervals() {
-  clearInterval();
+  if (alarmInterval) clearInterval(alarmInterval);
+  if (counterInterval) clearInterval(counterInterval);
+  alarmInterval = undefined;
   counterInterval = undefined;
 }
 
@@ -93,16 +96,21 @@ const stateMap = {
 
 function changeState() {
   if (stateMap[state]) stateMap[state]();
+  drawLabels();
+  draw();
 }
 
 function drawLabels() {
   g.clear();
   g.setFontAlign(-1, 0);
   g.setFont("6x8", 7);
-  g.drawString(`+  +`, 35, 180);
+  if (state != "started") // only when not runnung
+    g.drawString(`+  +`, 35, 180);
   g.setFontAlign(0, 0, 3);
   g.setFont("6x8", 1);
-  g.drawString(`reset                   (re)start`, 230, 120);
+  g.drawString("Reset                   (re)start", 230, 120);
+  if (state != "started") // only when not runnung
+    g.drawString("Back", 230, 120);
 }
 
 function resetTimer(value) {
@@ -130,8 +138,7 @@ function addWatch() {
   {
     repeat: false,
     edge: "falling",
-  },
-  );
+  });
   setWatch(
     () => {
       resetTimer(0);