diff --git a/src/editor/ui/Library.js b/src/editor/ui/Library.js
index 38ef670..36ae3df 100644
--- a/src/editor/ui/Library.js
+++ b/src/editor/ui/Library.js
@@ -454,7 +454,10 @@ export default class Library {
             }
 
             tb.className = 'assetbox on';
-            selectedOne = tb.id;
+            // to avoid double click
+            setTimeout(function () {
+                selectedOne = tb.id;
+            }, 200);
             clickThumb = tb;
             if (tb.fieldname) {
                 gn('assetname').textContent = tb.fieldname;
diff --git a/src/entry/inapp.js b/src/entry/inapp.js
index 71e3094..fe84cb8 100644
--- a/src/entry/inapp.js
+++ b/src/entry/inapp.js
@@ -75,7 +75,6 @@ export function inappInterfaceGuide () {
             window.parent.ScratchAudio.sndFXWithVolume('keydown.wav', 0.3);
         }
     };
-    document.addEventListener('touchstart', switchHelp, false);
     document.addEventListener('click', switchHelp, false);
 }
 
@@ -126,7 +125,6 @@ export function inappPaintEditorGuide () {
             window.parent.ScratchAudio.sndFXWithVolume('keydown.wav', 0.3);
         }
     };
-    document.addEventListener('touchstart', switchHelp, false);
     document.addEventListener('click', switchHelp, false);
 }