diff --git a/Pixiview.iOS/AppDelegate.cs b/Pixiview.iOS/AppDelegate.cs
index ce788b0..455b65e 100644
--- a/Pixiview.iOS/AppDelegate.cs
+++ b/Pixiview.iOS/AppDelegate.cs
@@ -26,7 +26,9 @@ namespace Pixiview.iOS
 
         public override bool OpenUrl(UIApplication app, NSUrl url, NSDictionary options)
         {
+#if DEBUG
             App.DebugPrint($"url: {url}.");
+#endif
             return App.OpenUrl(url);
         }
     }
diff --git a/Pixiview/App.cs b/Pixiview/App.cs
index 926dfeb..614dee7 100644
--- a/Pixiview/App.cs
+++ b/Pixiview/App.cs
@@ -44,7 +44,9 @@ namespace Pixiview
                 if (!string.IsNullOrEmpty(host) && port > 0)
                 {
                     Configs.Proxy = new System.Net.WebProxy(host, port);
+#if DEBUG
                     DebugPrint($"load proxy: {host}:{port}");
+#endif
                 }
                 else
                 {
@@ -74,7 +76,9 @@ namespace Pixiview
             {
                 return;
             }
+#if DEBUG
             DebugPrint($"application theme: {theme}");
+#endif
             ThemeBase themeInstance;
             if (theme == AppTheme.Dark)
             {
diff --git a/Pixiview/AppShell.xaml.cs b/Pixiview/AppShell.xaml.cs
index e1da9c3..cd5e428 100644
--- a/Pixiview/AppShell.xaml.cs
+++ b/Pixiview/AppShell.xaml.cs
@@ -57,7 +57,10 @@ namespace Pixiview
             BindingContext = this;
             InitializeComponent();
 
+#if DEBUG
             App.DebugPrint($"folder: {Stores.PersonalFolder}");
+            App.DebugPrint($"cache: {Stores.CacheFolder}");
+#endif
         }
 
         protected override void OnNavigated(ShellNavigatedEventArgs args)
diff --git a/Pixiview/Illust/FavoritesPage.xaml.cs b/Pixiview/Illust/FavoritesPage.xaml.cs
index ab47677..429635c 100644
--- a/Pixiview/Illust/FavoritesPage.xaml.cs
+++ b/Pixiview/Illust/FavoritesPage.xaml.cs
@@ -280,14 +280,18 @@ namespace Pixiview.Illust
                         if (bookmarkId != null)
                         {
                             // not exists in remote any more
+#if DEBUG
                             App.DebugPrint($"remove bookmark ({bookmarkId}) - {b.Id}: {b.Title}");
+#endif
                             nows.RemoveAt(i);
                         }
                     }
                     else if (bookmarkId != bookmark.BookmarkId)
                     {
                         // update bookmark id
+#if DEBUG
                         App.DebugPrint($"change bookmark ({bookmarkId}) to ({bookmark.BookmarkId}) - {b.Id}: {b.Title}");
+#endif
                         b.BookmarkId = bookmark.BookmarkId;
                     }
                 }
@@ -299,7 +303,9 @@ namespace Pixiview.Illust
                     for (var i = 0; i < list.Length; i++)
                     {
                         var item = list[i];
+#if DEBUG
                         App.DebugPrint($"add bookmark ({item.BookmarkId}) - {item.Id}: {item.Title}");
+#endif
                         item.Image = StyleDefinition.DownloadBackground;
                     }
                     nows.InsertRange(0, list);
diff --git a/Pixiview/Illust/IllustCollectionPage.cs b/Pixiview/Illust/IllustCollectionPage.cs
index 490a718..21c04ab 100644
--- a/Pixiview/Illust/IllustCollectionPage.cs
+++ b/Pixiview/Illust/IllustCollectionPage.cs
@@ -166,7 +166,9 @@ namespace Pixiview.Illust
             if (Columns != columns)
             {
                 Columns = columns;
+#if DEBUG
                 App.DebugPrint($"change columns to {columns}");
+#endif
             }
         }
 
@@ -521,7 +523,9 @@ namespace Pixiview.Illust
 
         protected void DoLoadIllusts(bool force = false, bool bottom = false)
         {
+#if DEBUG
             App.DebugPrint($"start loading data, force: {force}");
+#endif
             illustData = DoLoadIllustData(force);
             if (illustData == null)
             {
@@ -702,7 +706,9 @@ namespace Pixiview.Illust
                     if (CheckRefresh())
                     {
                         lastRefreshY = y;
+#if DEBUG
                         App.DebugPrint("start to load next page");
+#endif
                         StartLoad(true, true);
                     }
                 }
diff --git a/Pixiview/Illust/RankingPage.xaml.cs b/Pixiview/Illust/RankingPage.xaml.cs
index 8663e4b..9dad8eb 100644
--- a/Pixiview/Illust/RankingPage.xaml.cs
+++ b/Pixiview/Illust/RankingPage.xaml.cs
@@ -320,7 +320,9 @@ namespace Pixiview.Illust
             if (nextPage == currentPage + 1)
             {
                 currentPage = nextPage;
+#if DEBUG
                 App.DebugPrint($"loading page {nextPage}");
+#endif
                 return true;
             }
             return false;
@@ -353,7 +355,9 @@ namespace Pixiview.Illust
             {
                 // query changed.
                 lastQueryKey = query;
+#if DEBUG
                 App.DebugPrint($"query changed: {query}");
+#endif
                 PrepareLoad();
             }
         }
diff --git a/Pixiview/Illust/RecommendsPage.xaml.cs b/Pixiview/Illust/RecommendsPage.xaml.cs
index 4e4221d..b7f8eb5 100644
--- a/Pixiview/Illust/RecommendsPage.xaml.cs
+++ b/Pixiview/Illust/RecommendsPage.xaml.cs
@@ -190,7 +190,9 @@ namespace Pixiview.Illust
             if (UserColumns != columns)
             {
                 UserColumns = columns;
+#if DEBUG
                 App.DebugPrint($"change user columns to {columns}");
+#endif
             }
         }
 
diff --git a/Pixiview/Illust/RelatedIllustsPage.xaml.cs b/Pixiview/Illust/RelatedIllustsPage.xaml.cs
index b34ce2e..815e4ce 100644
--- a/Pixiview/Illust/RelatedIllustsPage.xaml.cs
+++ b/Pixiview/Illust/RelatedIllustsPage.xaml.cs
@@ -64,7 +64,9 @@ namespace Pixiview.Illust
                 if (ids.Length == 0 || nextIndex >= illustIds.Length)
                 {
                     // done
+#if DEBUG
                     App.DebugPrint($"download completed: {startIndex}");
+#endif
                     startIndex = nextIndex;
                 }
             }
diff --git a/Pixiview/Illust/UserIllustPage.xaml.cs b/Pixiview/Illust/UserIllustPage.xaml.cs
index bf7d77e..5f80b9e 100644
--- a/Pixiview/Illust/UserIllustPage.xaml.cs
+++ b/Pixiview/Illust/UserIllustPage.xaml.cs
@@ -61,7 +61,9 @@ namespace Pixiview.Illust
                     return null;
                 }
                 illustIds = init.body.illusts.Keys.OrderByDescending(i => int.TryParse(i, out int id) ? id : -1).ToArray();
+#if DEBUG
                 App.DebugPrint($"user has ({illustIds.Length}) illusts.");
+#endif
                 startIndex = 0;
             }
 
@@ -75,7 +77,9 @@ namespace Pixiview.Illust
             if (ids.Length == 0 || nextIndex >= illustIds.Length)
             {
                 // done
+#if DEBUG
                 App.DebugPrint($"download completed: {startIndex}");
+#endif
                 startIndex = nextIndex;
             }
             return data;
diff --git a/Pixiview/Illust/ViewIllustPage.xaml.cs b/Pixiview/Illust/ViewIllustPage.xaml.cs
index 90c43e8..4bab17d 100644
--- a/Pixiview/Illust/ViewIllustPage.xaml.cs
+++ b/Pixiview/Illust/ViewIllustPage.xaml.cs
@@ -353,7 +353,9 @@ namespace Pixiview.Illust
             var reload = false;
             if (pages.body.Length > items.Length)
             {
+#if DEBUG
                 App.DebugPrint($"local page count ({items.Length}) is not equals the remote one ({pages.body.Length})");
+#endif
                 var tmp = new IllustDetailItem[pages.body.Length];
                 items.CopyTo(items, 0);
 #if __IOS__
@@ -430,7 +432,9 @@ namespace Pixiview.Illust
             {
                 if (item.Loading || item.Image != null)
                 {
+#if DEBUG
                     App.DebugPrint($"skipped, loading or already loaded, index: {index}, loading: {item.Loading}");
+#endif
                     return;
                 }
             }
diff --git a/Pixiview/OptionPage.xaml.cs b/Pixiview/OptionPage.xaml.cs
index d7df4e8..127baf3 100644
--- a/Pixiview/OptionPage.xaml.cs
+++ b/Pixiview/OptionPage.xaml.cs
@@ -102,14 +102,18 @@ namespace Pixiview
             {
                 Preferences.Set(Configs.IsOnR18Key, r18);
                 Configs.IsOnR18 = r18;
+#if DEBUG
                 App.DebugPrint($"r-18 filter: {r18}");
+#endif
             }
 
             if ((int)Configs.SyncFavType != syncType)
             {
                 Preferences.Set(Configs.SyncFavTypeKey, syncType);
                 Configs.SyncFavType = (SyncType)syncType;
+#if DEBUG
                 App.DebugPrint($"favorite sync type changed to {Configs.SyncFavType}");
+#endif
             }
 
             var proxy = Configs.Proxy;
@@ -130,7 +134,9 @@ namespace Pixiview
                     if (!string.IsNullOrEmpty(h) && pt > 0)
                     {
                         Configs.Proxy = new System.Net.WebProxy(h, pt);
+#if DEBUG
                         App.DebugPrint($"set proxy to: {h}:{pt}");
+#endif
                     }
                 }
             }
@@ -145,7 +151,9 @@ namespace Pixiview
                 if (proxy != null)
                 {
                     Configs.Proxy = null;
+#if DEBUG
                     App.DebugPrint("clear proxy");
+#endif
                 }
             }
 
@@ -162,8 +170,9 @@ namespace Pixiview
                     {
                         session = session.Substring(0, index);
                         Configs.SetUserId(session, true);
-
+#if DEBUG
                         App.DebugPrint($"cookie changed, user id: {session}");
+#endif
                     }
                 }
             }
diff --git a/Pixiview/UI/AdaptedPage.cs b/Pixiview/UI/AdaptedPage.cs
index a65c891..808f708 100644
--- a/Pixiview/UI/AdaptedPage.cs
+++ b/Pixiview/UI/AdaptedPage.cs
@@ -132,7 +132,9 @@ namespace Pixiview.UI
         {
             if (Tap.IsBusy)
             {
+#if DEBUG
                 App.DebugPrint("gesture recognizer is now busy...");
+#endif
                 return;
             }
             using (Tap.Start())
diff --git a/Pixiview/Utils/EnvironmentService.cs b/Pixiview/Utils/EnvironmentService.cs
index 1bff761..2c3e601 100644
--- a/Pixiview/Utils/EnvironmentService.cs
+++ b/Pixiview/Utils/EnvironmentService.cs
@@ -109,8 +109,9 @@ namespace Pixiview.Utils
         {
             Thread.CurrentThread.CurrentCulture = ci;
             Thread.CurrentThread.CurrentUICulture = ci;
-
+#if DEBUG
             App.DebugPrint($"CurrentCulture set: {ci.Name}");
+#endif
         }
 
         public static CultureInfo GetCurrentCultureInfo()
@@ -179,7 +180,9 @@ namespace Pixiview.Utils
                     break;
             }
 
+#if DEBUG
             App.DebugPrint($"iOS Language: {iOSLanguage}, .NET Language/Locale: {netLanguage}");
+#endif
             return netLanguage;
         }
 #elif __ANDROID__
@@ -207,7 +210,9 @@ namespace Pixiview.Utils
                     netLanguage = androidLanguage;
                     break;
             }
+#if DEBUG
             App.DebugPrint($"Android Language: {androidLanguage}, .NET Language/Locale: {netLanguage}");
+#endif
             return netLanguage;
         }
 #endif
@@ -232,7 +237,9 @@ namespace Pixiview.Utils
                     break;
             }
 
+#if DEBUG
             App.DebugPrint($".NET Fallback Language/Locale: {platCulture.LanguageCode} to {netLanguage} (application-specific)");
+#endif
             return netLanguage;
         }
 
diff --git a/Pixiview/Utils/Extensions.cs b/Pixiview/Utils/Extensions.cs
index 4782a1f..8702cbe 100644
--- a/Pixiview/Utils/Extensions.cs
+++ b/Pixiview/Utils/Extensions.cs
@@ -152,7 +152,9 @@ namespace Pixiview.Utils
                     }
                     if (disposed)
                     {
+#if DEBUG
                         App.DebugPrint($"parallel task determinate, disposed");
+#endif
                         return;
                     }
                     Thread.Sleep(100);
@@ -183,7 +185,9 @@ namespace Pixiview.Utils
                     }
                 });
             }
+#if DEBUG
             App.DebugPrint($"parallel task done");
+#endif
             complete?.Invoke();
         }
 
diff --git a/Pixiview/Utils/Stores.cs b/Pixiview/Utils/Stores.cs
index 76caf29..ccf1700 100644
--- a/Pixiview/Utils/Stores.cs
+++ b/Pixiview/Utils/Stores.cs
@@ -16,11 +16,7 @@ namespace Pixiview.Utils
     public static class Stores
     {
         public static readonly string PersonalFolder = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
-#if __IOS__
-        public static readonly string CacheFolder = Environment.GetFolderPath(Environment.SpecialFolder.InternetCache);
-#else
         public static readonly string CacheFolder = FileSystem.CacheDirectory;
-#endif
 
         private const string favoriteFile = "favorites.json";
         private const string globalFile = "global.json";
@@ -98,14 +94,7 @@ namespace Pixiview.Utils
             var file = Path.Combine(PersonalFolder, ugoiraFolder, zip, frame);
             if (File.Exists(file))
             {
-                //try
-                //{
                 return file;
-                //}
-                //catch (Exception ex)
-                //{
-                //    App.DebugError("load.ugoira", $"failed to load ugoira frame: {zip}/{frame}, error: {ex.Message}");
-                //}
             }
             return null;
         }
@@ -314,7 +303,9 @@ namespace Pixiview.Utils
             }
             else
             {
+#if DEBUG
                 App.DebugPrint($"current csrf token: {result.token}");
+#endif
                 Configs.CsrfToken = result.token;
             }
             return result;
@@ -347,7 +338,9 @@ namespace Pixiview.Utils
             }
             else
             {
+#if DEBUG
                 App.DebugPrint($"successs, bookmark id: {result.body.last_bookmark_id}, status: {result.body.stacc_status_id}");
+#endif
                 return result.body.last_bookmark_id;
             }
             return null;
@@ -381,7 +374,9 @@ namespace Pixiview.Utils
                 App.DebugPrint("failed to delete bookmark, result is null");
                 return false;
             }
+#if DEBUG
             App.DebugPrint($"successs, delete bookmark");
+#endif
             return true;
         }
 
diff --git a/Pixiview/Utils/Ugoira.cs b/Pixiview/Utils/Ugoira.cs
index f648af9..04b67bf 100644
--- a/Pixiview/Utils/Ugoira.cs
+++ b/Pixiview/Utils/Ugoira.cs
@@ -178,7 +178,9 @@ namespace Pixiview.Utils
                 var url = ugoira.originalSrc;
                 var id = detailItem.Id;
                 var (size, lastModified, client) = HttpUtility.GetUgoiraHeader(url, id);
+#if DEBUG
                 App.DebugPrint($"starting download ugoira: {size} bytes, last modified: {lastModified}");
+#endif
 
                 var data = new byte[size];
 
@@ -284,7 +286,9 @@ namespace Pixiview.Utils
                 ParallelTask.Start(0, inSegs.Count, 2, i =>
                 {
                     var seg = inSegs[i];
+#if DEBUG
                     App.DebugPrint($"start to download segment #{seg.Index}, from {seg.From} to {seg.To} / {size}");
+#endif
                     using (var ms = new MemoryStream(data, (int)seg.From, seg.Count))
                     {
                         HttpUtility.DownloadUgoiraImage(client, url, id, lastModified, seg.From, seg.To, ms);
@@ -321,7 +325,9 @@ namespace Pixiview.Utils
                         }
                     }
                 }
+#if DEBUG
                 App.DebugPrint("download over");
+#endif
             }
         }