diff --git a/README.md b/README.md
index f1ee6ef1..7d3fd242 100644
--- a/README.md
+++ b/README.md
@@ -3,18 +3,17 @@
 [![Build Status](https://api.travis-ci.org/shadowsocks/shadowsocks-android.svg)](https://travis-ci.org/shadowsocks/shadowsocks-android)
 [![Releases](https://img.shields.io/github/downloads/shadowsocks/shadowsocks-android/total.svg)](https://github.com/shadowsocks/shadowsocks-android/releases)
 
-A [shadowsocks](http://shadowsocks.org) client for Android, written in Scala.  
+A [shadowsocks](http://shadowsocks.org) client for Android, written in Kotlin.  
 <a href="https://play.google.com/store/apps/details?id=com.github.shadowsocks"><img src="https://play.google.com/intl/en_us/badges/images/generic/en-play-badge.png" height="48"></a>
 
 
 ### PREREQUISITES
 
 * JDK 1.8
-* SBT 0.13.0+
 * Go 1.4+
 * Android SDK
   - Build Tools 26+
-  - Android Support Repository and Google Repository (see `build.sbt` for version)
+  - Android Support Repository and Google Repository (see `build.gradle` for version)
   - Android NDK r16+
 
 ### BUILD
diff --git a/mobile/src/main/assets/pages/about.html b/mobile/src/main/assets/pages/about.html
index 8cb0b6ee..f1e9b66d 100644
--- a/mobile/src/main/assets/pages/about.html
+++ b/mobile/src/main/assets/pages/about.html
@@ -273,7 +273,7 @@ img {
 </style>
 </head>
 <body>
-<p>A <a href="http://shadowsocks.org">Shadowsocks</a> client for Android, written in Scala.</p>
+<p>A <a href="http://shadowsocks.org">Shadowsocks</a> client for Android, written in Kotlin.</p>
 <p>Copyright (C) 2017 by Max Lv <a href="&#x6d;&#97;&#x69;&#108;&#116;&#111;&#x3a;&#x6d;&#97;x&#46;&#99;.&#108;&#118;&#x40;&#103;&#109;&#97;&#x69;&#108;&#46;&#x63;&#x6f;&#109;">&#x6d;&#97;&#x78;.&#x63;&#x2e;&#108;v&#64;&#x67;&#109;&#x61;&#x69;&#108;&#x2e;&#99;&#111;&#109;</a></p>
 <p>Copyright (C) 2017 by Mygod Studio <a href="mailto:contact-shadowsocks-android@mygod.be">contact-shadowsocks-android@mygod.be</a></p>
 <p>This program is free software: you can redistribute it and/or modify
diff --git a/plugin/doc.md b/plugin/doc.md
index b88904b0..395dfe11 100644
--- a/plugin/doc.md
+++ b/plugin/doc.md
@@ -196,7 +196,7 @@ This feature hasn't been implemented yet.
 Plugins are certified using package signatures and shadowsocks-android will consider these
  signatures as trusted:
 
-* Signatures by [trusted sources](/mobile/src/main/scala/com/github/shadowsocks/plugin/PluginManager.scala#L22)
+* Signatures by [trusted sources](/mobile/src/main/java/com/github/shadowsocks/plugin/PluginManager.kt#L39)
   which includes:
   - @madeye, i.e. the signer of the main repo;
   - The main repo doesn't contain any other trusted signatures. Third-party forks should add their