diff --git a/src/index.tpl b/src/index.tpl
index 70bfca5..f423dce 100644
--- a/src/index.tpl
+++ b/src/index.tpl
@@ -9,5 +9,17 @@
   </head>
   <body>
     <div id="app"></div>
+    <script async>
+      var el = document.createElement('div')
+      el.style.width = '100vw'
+      if (el.style.width !== '100vw') {
+        var msg = [
+          'Sorry, this browser is not supported by WEBXOSS :(',
+          'For Android <= 4.3, please download Google Chrome.',
+          'For iOS <= 7, please update your system.',
+        ].join('\n')
+        window.alert(msg)
+      }
+    </script>
   </body>
 </html>
\ No newline at end of file
diff --git a/webpack.config.js b/webpack.config.js
index bf60fcf..ac35a99 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -36,9 +36,9 @@ const TESTS = {
 }
 let browsers = [
   'last 2 versions',
-  'ie >= 10',
+  'ie >= 11',
   'Firefox ESR',
-  'Android >= 4.3',
+  'Android >= 4.4',
   'iOS >= 8',
   'last 2 ChromeAndroid versions',
 ].join(', ')
