diff --git a/README.md b/README.md
index 31f208a..2039319 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,9 @@ SKPhotoBrowser
 
 Simple PhotoBrowser/Viewer inspired by facebook, twitter photo browsers written by swift, based on [IDMPhotoBrowser](https://github.com/ideaismobile/IDMPhotoBrowser), [MWPhotoBrowser](https://github.com/mwaterfall/MWPhotoBrowser).
 
+## Attention
+- released v3.0.x and this version goes some breaking changes. please check [CHANGELOG](https://github.com/suzuki-0000/SKPhotoBrowser/blob/master/CHANGELOG.md).
+
 ## features
 - Display one or more images by providing either `UIImage` objects, or string of URL array.
 - Photos can be zoomed and panned, and optional captions can be displayed
diff --git a/SKPhotoBrowser.podspec b/SKPhotoBrowser.podspec
index f1fc5c3..7e8b247 100644
--- a/SKPhotoBrowser.podspec
+++ b/SKPhotoBrowser.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "SKPhotoBrowser"
-  s.version      = "2.1.0"
+  s.version      = "3.0.0"
   s.summary      = "Simple PhotoBrowser/Viewer inspired by facebook, twitter photo browsers written by swift2.0."
   s.homepage     = "https://github.com/suzuki-0000/SKPhotoBrowser"
   s.license      = { :type => "MIT", :file => "LICENSE" }